Later this month I'm going away for about 5 weeks. I will just
disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
If I just leave it, there is a good chance that it will be pretty flat
when I get back, but it's undesirable to disconnect it with all the
electronic gubbins on it. Any opinions about leaving it on a trickle
charger?

On 1/8/2022 4:54 pm, keithr0 wrote:
> Later this month I'm going away for about 5 weeks. I will just
> disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
> If I just leave it, there is a good chance that it will be pretty flat
> when I get back, but it's undesirable to disconnect it with all the
> electronic gubbins on it. Any opinions about leaving it on a trickle
> charger?

I would leave it on a trickle charger provided the charger is designed
to be left connected for long periods.
Don't know about the Mazda 3 but some cars don't like being disconnected
from power for a long time, MB particularly don't like it, I recently
had to replace my battery and I had to clear about 15 "low voltage"
fault codes when I refitted the new battery.
The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it was
replaced FOC under warranty.

--
Daryl

On 8/1/2022 5:05 PM, Daryl wrote:
> On 1/8/2022 4:54 pm, keithr0 wrote:
>> Later this month I'm going away for about 5 weeks. I will just
>> disconnect the battery on the MX-5, but I'm not sure about the Mazda
>> 3. If I just leave it, there is a good chance that it will be pretty
>> flat when I get back, but it's undesirable to disconnect it with all
>> the electronic gubbins on it. Any opinions about leaving it on a
>> trickle charger?
>
>
> I would leave it on a trickle charger provided the charger is designed
> to be left connected for long periods.
~~~~~~~~~~~~~~~~
Yep, do it!.

> Don't know about the Mazda 3 but some cars don't like being disconnected
> from power for a long time, MB particularly don't like it, I recently
> had to replace my battery and I had to clear about 15 "low voltage"
> fault codes when I refitted the new battery.
> The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it was
> replaced FOC under warranty.
>

On 1/8/2022 4:54 pm, keithr0 wrote:
> Later this month I'm going away for about 5 weeks. I will just
> disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
> If I just leave it, there is a good chance that it will be pretty flat
> when I get back, but it's undesirable to disconnect it with all the
> electronic gubbins on it. Any opinions about leaving it on a trickle
> charger?

It's what I would do. Get an intelligent charger that does trickle and
float for best results.

BTW, does it have *that much* idle current draw on it? My mate leaves
his Prius for a couple of months at a time with no real issues.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 1/08/2022 5:50 pm, Xeno wrote:
> On 1/8/2022 4:54 pm, keithr0 wrote:
>> Later this month I'm going away for about 5 weeks. I will just
>> disconnect the battery on the MX-5, but I'm not sure about the Mazda
>> 3. If I just leave it, there is a good chance that it will be pretty
>> flat when I get back, but it's undesirable to disconnect it with all
>> the electronic gubbins on it. Any opinions about leaving it on a
>> trickle charger?
>
> It's what I would do. Get an intelligent charger that does trickle and
> float for best results.
>
> BTW, does it have *that much* idle current draw on it? My mate leaves
> his Prius for a couple of months at a time with no real issues.
>

I wouldn't think it's necessary to disconnect a battery just because
it's not being driven for five weeks.

--
https://tinyurl.com/Yosemite-Sam

FUCK PUTIN!!

On 1/8/2022 7:35 pm, Yosemite Sam wrote:
> On 1/08/2022 5:50 pm, Xeno wrote:
>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>> Later this month I'm going away for about 5 weeks. I will just
>>> disconnect the battery on the MX-5, but I'm not sure about the Mazda
>>> 3. If I just leave it, there is a good chance that it will be pretty
>>> flat when I get back, but it's undesirable to disconnect it with all
>>> the electronic gubbins on it. Any opinions about leaving it on a
>>> trickle charger?
>>
>> It's what I would do. Get an intelligent charger that does trickle and
>> float for best results.
>>
>> BTW, does it have *that much* idle current draw on it? My mate leaves
>> his Prius for a couple of months at a time with no real issues.
>>
>
> I wouldn't think it's necessary to disconnect a battery just because
> it's not being driven for five weeks.
>
>
Normally not but parasitic draw is the $64 question in play here. Some
cars have more than others and that will determine the ability to
restart the car on return. Given the vintage of the MX-5 in question, I
would expect a parasitic drain on the battery to be about 20 milliamps.
Any great deal more than 20 milliamps and the battery may well not last
the distance.

With the Mazda 3, on the other hand, life gets a little more complex.
The parasitic drain on the 3 is notionally 10 milliamps. The caveat is
that it will only be 10 milliamps *if* the Body Control Module (BCM)
goes to sleep. The BCM won't go to sleep if it sees some circuits still
active, the most common of such circuits is the remote door locking
system. Here's the rub, to make the BCM go to sleep you need to *lock
the doors*. With the BCM active the parasitic draw will be somewhere
between 50 milliamps and 100 milliamps. That's hefty and will flatten
the battery over a time span of a month or two or, at the very least,
not leave enough charge to allow the engine to start. Remember, the ECM
wants to see a *minimum* voltage in the battery and if it isn't there,
it won't allow an engine start. Ah, the joys of "intelligent" systems!

A lot of cars have a BCM that needs to go to sleep and the fitting of
aftermarket accessories can result in the BCM not going to sleep even
when the doors are locked. I prefer to leave my car unlocked whilst it
is in the garage. I just take the keys out and plant them somewhere
safe. But then, my car is a daily driver. I think the maximum it has sat
without a start has been a week. But I have an intelligent charger that
has trickle and float modes so, were I to leave my car idle for an
extended stay, say a month or more, then I would simply plug the charger
on to the battery. Not so doable however if you are leaving the car in,
say, an airport long term car park. But then, you'd most certainly have
the car locked - and there's always the RACQ.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 1/08/2022 4:54 pm, keithr0 wrote:

> Later this month I'm going away for about 5 weeks.

Going to give us a lecture about doing our bit for the environment when
you get back? :)

> I will just disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
> If I just leave it, there is a good chance that it will be pretty flat
> when I get back, but it's undesirable to disconnect it with all the
> electronic gubbins on it.

You won't harm the car by dropping the negative battery terminal off and
leaving it parked with the battery disconnected.

> Any opinions about leaving it on a trickle charger?

As long as it's a reputable charger that you'd feel comfortable leaving
connected while no one is around to monitor it. Ctek make a good range
of chargers, and unlike some "smart" chargers they will reset themselves
and resume where they left off if there is a power outage while you're
away.

Shop around, as you can generally buy their 5amp charger for not much
more than the 0.8A unit.

--
--
--
Regards,
Noddy.

On 1/8/2022 8:09 pm, Xeno wrote:
> On 1/8/2022 7:35 pm, Yosemite Sam wrote:
>> On 1/08/2022 5:50 pm, Xeno wrote:
>>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>>> Later this month I'm going away for about 5 weeks. I will just
>>>> disconnect the battery on the MX-5, but I'm not sure about the Mazda
>>>> 3. If I just leave it, there is a good chance that it will be pretty
>>>> flat when I get back, but it's undesirable to disconnect it with all
>>>> the electronic gubbins on it. Any opinions about leaving it on a
>>>> trickle charger?
>>>
>>> It's what I would do. Get an intelligent charger that does trickle
>>> and float for best results.
>>>
>>> BTW, does it have *that much* idle current draw on it? My mate leaves
>>> his Prius for a couple of months at a time with no real issues.
>>>
>>
>> I wouldn't think it's necessary to disconnect a battery just because
>> it's not being driven for five weeks.
>>
>>
> Normally not but parasitic draw is the $64 question in play here. Some
> cars have more than others and that will determine the ability to
> restart the car on return. Given the vintage of the MX-5 in question, I
> would expect a parasitic drain on the battery to be  about 20 milliamps.
> Any great deal more than 20 milliamps and the battery may well not last
> the distance.
>
> With the Mazda 3, on the other hand, life gets a little more complex.
> The parasitic drain on the 3 is notionally 10 milliamps. The caveat is
> that it will only be 10 milliamps *if* the Body Control Module (BCM)
> goes to sleep. The BCM won't go to sleep if it sees some circuits still
> active, the most common of such circuits is the remote door locking
> system. Here's the rub, to make the BCM go to sleep you need to *lock
> the doors*. With the BCM active the parasitic draw will be somewhere
> between 50 milliamps and 100 milliamps. That's hefty and will flatten
> the battery over a time span of a month or two or, at the very least,
> not leave enough charge to allow the engine to start. Remember, the ECM
> wants to see a *minimum* voltage in the battery and if it isn't there,
> it won't allow an engine start. Ah, the joys of "intelligent" systems!
>
> A lot of cars have a BCM that needs to go to sleep and the fitting of
> aftermarket accessories can result in the BCM not going to sleep even
> when the doors are locked. I prefer to leave my car unlocked whilst it
> is in the garage. I just take the keys out and plant them somewhere
> safe. But then, my car is a daily driver. I think the maximum it has sat
> without a start has been a week. But I have an intelligent charger that
> has trickle and float modes so, were I to leave my car idle for an
> extended stay, say a month or more, then I would simply plug the charger
> on to the battery. Not so doable however if you are leaving the car in,
> say, an airport long term car park. But then, you'd most certainly have
> the car locked - and there's always the RACQ.

Forgot to add, the Mazda 3, if I'm not mistaken, has that start/stop
bullshit and, as such, is equipped with an AGM 60AH or 65AH battery. A
battery of that size, if in good nick, should be more than adequate to
deal with a nominal 10 milliamp parasitic drain over a few weeks. Just
do the math! Keith should just lock the doors, leave the battery
connected, and just enjoy his time away. Stressing over nothing!

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

keithr0 wrote:
>
>Later this month I'm going away for about 5 weeks. I will just
>disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
>If I just leave it, there is a good chance that it will be pretty flat
>when I get back, but it's undesirable to disconnect it with all the
>electronic gubbins on it. Any opinions about leaving it on a trickle
>charger?

If it's only for 5 weeks and the battery is in good condition you
should be able to leave it connected so long as there's no significant
parasitic losses which you can easily check with a multimeter.

Whatever you do don't connect a smart charger to your car, especially
the cheap Chinese ones from ebay which are relatively crude switch
mode devices that have the potential (pun intended) to do serious
damage to your car's electronics should the smart part fail for any
reason. Nor will they restart after a power flicker (which are common
where I am).

If you want to leave the car stand for long periods best option is to
replace the battery with a calcium which have a vastly lower self
discharge rate than conventional lead acid. They also last
considerably longer. My car frequently remains in the shed for the
entire northern wet season without battery issues.

Other thing to watch out for is rodents. Light aircraft owners I've
known swear by cloves.

--
John H

On 1/08/2022 5:05 pm, Daryl wrote:
> On 1/8/2022 4:54 pm, keithr0 wrote:
>> Later this month I'm going away for about 5 weeks. I will just
>> disconnect the battery on the MX-5, but I'm not sure about the Mazda
>> 3. If I just leave it, there is a good chance that it will be pretty
>> flat when I get back, but it's undesirable to disconnect it with all
>> the electronic gubbins on it. Any opinions about leaving it on a
>> trickle charger?
>
>
> I would leave it on a trickle charger provided the charger is designed
> to be left connected for long periods.

I would think connecting any sort of charger to a battery in situ would
be a big no-no.

> Don't know about the Mazda 3 but some cars don't like being
> disconnected from power for a long time, MB particularly don't like
> it, I recently had to replace my battery and I had to clear about 15
> "low voltage" fault codes when I refitted the new battery.
> The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it
> was replaced FOC under warranty.
>

--
https://tinyurl.com/Yosemite-Sam

FUCK PUTIN!!

On 1/08/2022 8:30 pm, Xeno wrote:
> On 1/8/2022 8:09 pm, Xeno wrote:
>> On 1/8/2022 7:35 pm, Yosemite Sam wrote:
>>> On 1/08/2022 5:50 pm, Xeno wrote:
>>>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>>>> Later this month I'm going away for about 5 weeks. I will just
>>>>> disconnect the battery on the MX-5, but I'm not sure about the
>>>>> Mazda 3. If I just leave it, there is a good chance that it will
>>>>> be pretty flat when I get back, but it's undesirable to disconnect
>>>>> it with all the electronic gubbins on it. Any opinions about
>>>>> leaving it on a trickle charger?
>>>>
>>>> It's what I would do. Get an intelligent charger that does trickle
>>>> and float for best results.
>>>>
>>>> BTW, does it have *that much* idle current draw on it? My mate
>>>> leaves his Prius for a couple of months at a time with no real issues.
>>>>
>>>
>>> I wouldn't think it's necessary to disconnect a battery just because
>>> it's not being driven for five weeks.
>>>
>>>
>> Normally not but parasitic draw is the $64 question in play here.
>> Some cars have more than others and that will determine the ability
>> to restart the car on return. Given the vintage of the MX-5 in
>> question, I would expect a parasitic drain on the battery to be 
>> about 20 milliamps. Any great deal more than 20 milliamps and the
>> battery may well not last the distance.
>>
>> With the Mazda 3, on the other hand, life gets a little more complex.
>> The parasitic drain on the 3 is notionally 10 milliamps. The caveat
>> is that it will only be 10 milliamps *if* the Body Control Module
>> (BCM) goes to sleep. The BCM won't go to sleep if it sees some
>> circuits still active, the most common of such circuits is the remote
>> door locking system. Here's the rub, to make the BCM go to sleep you
>> need to *lock the doors*. With the BCM active the parasitic draw will
>> be somewhere between 50 milliamps and 100 milliamps. That's hefty and
>> will flatten the battery over a time span of a month or two or, at
>> the very least, not leave enough charge to allow the engine to start.
>> Remember, the ECM wants to see a *minimum* voltage in the battery and
>> if it isn't there, it won't allow an engine start. Ah, the joys of
>> "intelligent" systems!
>>
>> A lot of cars have a BCM that needs to go to sleep and the fitting of
>> aftermarket accessories can result in the BCM not going to sleep even
>> when the doors are locked. I prefer to leave my car unlocked whilst
>> it is in the garage. I just take the keys out and plant them
>> somewhere safe. But then, my car is a daily driver. I think the
>> maximum it has sat without a start has been a week. But I have an
>> intelligent charger that has trickle and float modes so, were I to
>> leave my car idle for an extended stay, say a month or more, then I
>> would simply plug the charger on to the battery. Not so doable
>> however if you are leaving the car in, say, an airport long term car
>> park. But then, you'd most certainly have the car locked - and
>> there's always the RACQ.
>
> Forgot to add, the Mazda 3, if I'm not mistaken, has that start/stop
> bullshit and, as such, is equipped with an AGM 60AH or 65AH battery. A
> battery of that size, if in good nick, should be more than adequate to
> deal with a nominal 10 milliamp parasitic drain over a few weeks. Just
> do the math! Keith should just lock the doors, leave the battery
> connected, and just enjoy his time away. Stressing over nothing!
>
>

seems hard to believe any modern car would have a flat battery after
just five weeks of sitting idle

--
https://tinyurl.com/Yosemite-Sam

FUCK PUTIN!!

Daryl wrote:
>
>The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it was
>replaced FOC under warranty.

Interesting. Our German mechanic reckons I've been buying shit
batteries since they only last five years or so (calciums)... which is
pretty good in a hot climate (they'd probably last a couple of years
longer in Tassie).

I've long suspected that OEM batteries (and tyres) are better than
their replacements in the same brand but 18 years is ridiculous...
unless the huns know something the rest of world doesn't. :)

--
John H

On 2/8/2022 8:16 am, John_H wrote:
> keithr0 wrote:
>>
>> Later this month I'm going away for about 5 weeks. I will just
>> disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
>> If I just leave it, there is a good chance that it will be pretty flat
>> when I get back, but it's undesirable to disconnect it with all the
>> electronic gubbins on it. Any opinions about leaving it on a trickle
>> charger?
>
> If it's only for 5 weeks and the battery is in good condition you
> should be able to leave it connected so long as there's no significant
> parasitic losses which you can easily check with a multimeter.

The BCM may not cease its parasitic losses immediately the car is
locked. It may take a half hour or more for the system to settle down
and go to sleep and until then you won't get a true reading.
>
> Whatever you do don't connect a smart charger to your car, especially
> the cheap Chinese ones from ebay which are relatively crude switch
> mode devices that have the potential (pun intended) to do serious
> damage to your car's electronics should the smart part fail for any
> reason. Nor will they restart after a power flicker (which are common
> where I am).

Yeah, the cheap ones are only good for charging up a disconnected
battery - which is what I use mine for. I have a lithium-ion jump
starter in the car should the battery ever go flat. I use my cheapie
smart charger for doing a full top up on the NBN battery now and then,
my unintelligent 12V charger being a little too aggressive for those.
The NBN box charging system doesn't do a proper full charge, a common
feature of those things apparently, so I charge a spare and swap them
over regularly.
>
> If you want to leave the car stand for long periods best option is to
> replace the battery with a calcium which have a vastly lower self
> discharge rate than conventional lead acid. They also last
> considerably longer. My car frequently remains in the shed for the
> entire northern wet season without battery issues.

The Mazda 3 will already have a heavy duty battery for the stop/start
system and, depending on the model, an AGM. 5 weeks shouldn't be a
problem, especially if the car is locked and the BCM goes into sleep mode.
>
> Other thing to watch out for is rodents. Light aircraft owners I've
> known swear by cloves.
>
That's a handy tip. I'll pass that along to a farmer friend of mine. His
son's Nissan Skyline GTR became a rodent chewtoy while it was parked out
of service.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 2/8/2022 11:57 am, Yosemite Sam wrote:
> On 1/08/2022 5:05 pm, Daryl wrote:
>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>> Later this month I'm going away for about 5 weeks. I will just
>>> disconnect the battery on the MX-5, but I'm not sure about the Mazda
>>> 3. If I just leave it, there is a good chance that it will be pretty
>>> flat when I get back, but it's undesirable to disconnect it with all
>>> the electronic gubbins on it. Any opinions about leaving it on a
>>> trickle charger?
>>
>>
>> I would leave it on a trickle charger provided the charger is designed
>> to be left connected for long periods.
>
>
> I would think connecting any sort of charger to a battery in situ would
> be a big no-no.
>
Generally, as long as the charger is switched off at connection time,
shouldn't be an issue.
>
>> Don't know about the Mazda 3 but some cars don't like being
>> disconnected from power for a long time, MB particularly don't like
>> it, I recently had to replace my battery and I had to clear about 15
>> "low voltage" fault codes when I refitted the new battery.
>> The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it
>> was replaced FOC under warranty.
>>
>

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 2/8/2022 11:59 am, Yosemite Sam wrote:
> On 1/08/2022 8:30 pm, Xeno wrote:
>> On 1/8/2022 8:09 pm, Xeno wrote:
>>> On 1/8/2022 7:35 pm, Yosemite Sam wrote:
>>>> On 1/08/2022 5:50 pm, Xeno wrote:
>>>>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>>>>> Later this month I'm going away for about 5 weeks. I will just
>>>>>> disconnect the battery on the MX-5, but I'm not sure about the
>>>>>> Mazda 3. If I just leave it, there is a good chance that it will
>>>>>> be pretty flat when I get back, but it's undesirable to disconnect
>>>>>> it with all the electronic gubbins on it. Any opinions about
>>>>>> leaving it on a trickle charger?
>>>>>
>>>>> It's what I would do. Get an intelligent charger that does trickle
>>>>> and float for best results.
>>>>>
>>>>> BTW, does it have *that much* idle current draw on it? My mate
>>>>> leaves his Prius for a couple of months at a time with no real issues.
>>>>>
>>>>
>>>> I wouldn't think it's necessary to disconnect a battery just because
>>>> it's not being driven for five weeks.
>>>>
>>>>
>>> Normally not but parasitic draw is the $64 question in play here.
>>> Some cars have more than others and that will determine the ability
>>> to restart the car on return. Given the vintage of the MX-5 in
>>> question, I would expect a parasitic drain on the battery to be about
>>> 20 milliamps. Any great deal more than 20 milliamps and the battery
>>> may well not last the distance.
>>>
>>> With the Mazda 3, on the other hand, life gets a little more complex.
>>> The parasitic drain on the 3 is notionally 10 milliamps. The caveat
>>> is that it will only be 10 milliamps *if* the Body Control Module
>>> (BCM) goes to sleep. The BCM won't go to sleep if it sees some
>>> circuits still active, the most common of such circuits is the remote
>>> door locking system. Here's the rub, to make the BCM go to sleep you
>>> need to *lock the doors*. With the BCM active the parasitic draw will
>>> be somewhere between 50 milliamps and 100 milliamps. That's hefty and
>>> will flatten the battery over a time span of a month or two or, at
>>> the very least, not leave enough charge to allow the engine to start.
>>> Remember, the ECM wants to see a *minimum* voltage in the battery and
>>> if it isn't there, it won't allow an engine start. Ah, the joys of
>>> "intelligent" systems!
>>>
>>> A lot of cars have a BCM that needs to go to sleep and the fitting of
>>> aftermarket accessories can result in the BCM not going to sleep even
>>> when the doors are locked. I prefer to leave my car unlocked whilst
>>> it is in the garage. I just take the keys out and plant them
>>> somewhere safe. But then, my car is a daily driver. I think the
>>> maximum it has sat without a start has been a week. But I have an
>>> intelligent charger that has trickle and float modes so, were I to
>>> leave my car idle for an extended stay, say a month or more, then I
>>> would simply plug the charger on to the battery. Not so doable
>>> however if you are leaving the car in, say, an airport long term car
>>> park. But then, you'd most certainly have the car locked - and
>>> there's always the RACQ.
>>
>> Forgot to add, the Mazda 3, if I'm not mistaken, has that start/stop
>> bullshit and, as such, is equipped with an AGM 60AH or 65AH battery. A
>> battery of that size, if in good nick, should be more than adequate to
>> deal with a nominal 10 milliamp parasitic drain over a few weeks. Just
>> do the math! Keith should just lock the doors, leave the battery
>> connected, and just enjoy his time away. Stressing over nothing!
>>
>>
>
> seems hard to believe any modern car would have a flat battery after
> just five weeks of sitting idle
>
Happens a lot but, as my blurb above shows, there's usually an
explanation for it. A modern car, once the BCM goes into sleep mode,
should have a parasitic draw of no more than 20 milliamps and, more
typically, it should be in the region of 10 milliamps. A battery in
decent nick should go for two to three months with such a small draw and
still be able to start the car at the end of that time.

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 2/8/2022 12:10 pm, John_H wrote:
> Daryl wrote:
>>
>> The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it was
>> replaced FOC under warranty.
>
> Interesting. Our German mechanic reckons I've been buying shit
> batteries since they only last five years or so (calciums)... which is
> pretty good in a hot climate (they'd probably last a couple of years
> longer in Tassie).
>
> I've long suspected that OEM batteries (and tyres) are better than
> their replacements in the same brand but 18 years is ridiculous...
> unless the huns know something the rest of world doesn't. :)
>

When I first removed the old battery I noticed that it had MB stickers
on it, that didn't prove that it was the OE so I looked up the date code
and it was dated 2002, car was made in May 2002 so it appears to be the
OE battery.
When the new battery failed I removed it, found the receipt then took it
back to where I bought it, they stuffed around for 3 days deciding
whether or not it had completely failed then they consulted the supplier
and I was given a new replacement, I didn't like the car being
disconnected from power for too long so I connected the old battery via
jump leads and also connected my charger, after a few hours the old
battery was reading 14.3volts, the "new" one that failed wouldn't charge
past 10 volts.
After fitting the new battery I plugged in my scan tool and found 15
"low voltage" fault codes although no check engine light, MB doesn't
like low voltage.
Wife's Golf was made in 2016 and as far as I can tell its still got its
OE battery.

--
Daryl

On 2/08/2022 6:16 am, John_H wrote:
> keithr0 wrote:
>>
>> Later this month I'm going away for about 5 weeks. I will just
>> disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
>> If I just leave it, there is a good chance that it will be pretty flat
>> when I get back, but it's undesirable to disconnect it with all the
>> electronic gubbins on it. Any opinions about leaving it on a trickle
>> charger?
>
> If it's only for 5 weeks and the battery is in good condition you
> should be able to leave it connected so long as there's no significant
> parasitic losses which you can easily check with a multimeter.
>

But he should leave it for 5 minutes or so for the BCM to go to sleep.

> Whatever you do don't connect a smart charger to your car, especially
> the cheap Chinese ones from ebay which are relatively crude switch
> mode devices that have the potential (pun intended) to do serious
> damage to your car's electronics should the smart part fail for any
> reason. Nor will they restart after a power flicker (which are common
> where I am).
>

You can get good quality ones for a price but I wouldn't leave any
charging device connected for that long.

> If you want to leave the car stand for long periods best option is to
> replace the battery with a calcium which have a vastly lower self
> discharge rate than conventional lead acid. They also last
> considerably longer. My car frequently remains in the shed for the
> entire northern wet season without battery issues.
>
> Other thing to watch out for is rodents. Light aircraft owners I've
> known swear by cloves.
>

Yep a real problem and yes rats hate the smell of cloves.

--
keith on the 7 Oct 2021 wrote;
"He asserts that the claim is true, so, if
it is unproven, he is lying."

On 2/8/2022 2:27 pm, Clocky wrote:
> On 2/08/2022 6:16 am, John_H wrote:
>> keithr0 wrote:
>>>
>>> Later this month I'm going away for about 5 weeks. I will just
>>> disconnect the battery on the MX-5, but I'm not sure about the Mazda 3.
>>> If I just leave it, there is a good chance that it will be pretty flat
>>> when I get back, but it's undesirable to disconnect it with all the
>>> electronic gubbins on it. Any opinions about leaving it on a trickle
>>> charger?
>>
>> If it's only for 5 weeks and the battery is in good condition you
>> should be able to leave it connected so long as there's no significant
>> parasitic losses which you can easily check with a multimeter.
>>
>
> But he should leave it for 5 minutes or so for the BCM to go to sleep.

Some take longer - depending on what is attached, monitored and
controlled by them. Have no idea what the Mazda's BCM response time would be
>
>> Whatever you do don't connect a smart charger to your car, especially
>> the cheap Chinese ones from ebay which are relatively crude switch
>> mode devices that have the potential (pun intended) to do serious
>> damage to your car's electronics should the smart part fail for any
>> reason.  Nor will they restart after a power flicker (which are common
>> where I am).
>>
>
> You can get good quality ones for a price but I wouldn't leave any
> charging device connected for that long.

I have only a cheapie and I probably wouldn't connect it for a long time
unattended either. Never had to in the past as I have a proper
automotive charger for that, had it over 45 years too, well before smart
chargers. If I wanted to trickle charge an unattended car, I'd go and
buy a good quality one but I never leave my car unattended/driven for
long, thus far no longer than a week at any given time. And I have a
jump starter these days as well.
>
>> If you want to leave the car stand for long periods best option is to
>> replace the battery with a calcium which have a vastly lower self
>> discharge rate than conventional lead acid.  They also last
>> considerably longer.  My car frequently remains in the shed for the
>> entire northern wet season without battery issues.
>>
>> Other thing to watch out for is rodents.  Light aircraft owners I've
>> known swear by cloves.
>>
>
> Yep a real problem and yes rats hate the smell of cloves.
>
Only cloves around here are garlic cloves. ;-)

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)

On 2/08/2022 10:10 am, John_H wrote:
> Daryl wrote:
>>
>> The OE MB battery lasted 18yrs, the replacement 2.5 yrs, at least it was
>> replaced FOC under warranty.
>
> Interesting. Our German mechanic reckons I've been buying shit
> batteries since they only last five years or so (calciums)... which is
> pretty good in a hot climate (they'd probably last a couple of years
> longer in Tassie).
>
> I've long suspected that OEM batteries (and tyres) are better than
> their replacements in the same brand but 18 years is ridiculous...
> unless the huns know something the rest of world doesn't. :)
>

The genuine Toyota battery (also a Yaesu IIRC) in the Hilux lasted ~12
years. I replaced it with a new genuine Toyota battery out of a brand
new 70 series Landcuiser and I would expect at least the same life out
of that one.

My Hilux OEM pads have been replaced once and the vehicle has done over
350,000km. It's a real work ute with the battle scars to prove it, not
some poseur ute which makes the length of time the OEM parts lasted even
more remarkable.

--
keith on the 7 Oct 2021 wrote;
"He asserts that the claim is true, so, if
it is unproven, he is lying."

On 2/08/2022 9:59 am, Yosemite Sam wrote:
> On 1/08/2022 8:30 pm, Xeno wrote:
>> On 1/8/2022 8:09 pm, Xeno wrote:
>>> On 1/8/2022 7:35 pm, Yosemite Sam wrote:
>>>> On 1/08/2022 5:50 pm, Xeno wrote:
>>>>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>>>>> Later this month I'm going away for about 5 weeks. I will just
>>>>>> disconnect the battery on the MX-5, but I'm not sure about the
>>>>>> Mazda 3. If I just leave it, there is a good chance that it will
>>>>>> be pretty flat when I get back, but it's undesirable to disconnect
>>>>>> it with all the electronic gubbins on it. Any opinions about
>>>>>> leaving it on a trickle charger?
>>>>>
>>>>> It's what I would do. Get an intelligent charger that does trickle
>>>>> and float for best results.
>>>>>
>>>>> BTW, does it have *that much* idle current draw on it? My mate
>>>>> leaves his Prius for a couple of months at a time with no real issues.
>>>>>
>>>>
>>>> I wouldn't think it's necessary to disconnect a battery just because
>>>> it's not being driven for five weeks.
>>>>
>>>>
>>> Normally not but parasitic draw is the $64 question in play here.
>>> Some cars have more than others and that will determine the ability
>>> to restart the car on return. Given the vintage of the MX-5 in
>>> question, I would expect a parasitic drain on the battery to be about
>>> 20 milliamps. Any great deal more than 20 milliamps and the battery
>>> may well not last the distance.
>>>
>>> With the Mazda 3, on the other hand, life gets a little more complex.
>>> The parasitic drain on the 3 is notionally 10 milliamps. The caveat
>>> is that it will only be 10 milliamps *if* the Body Control Module
>>> (BCM) goes to sleep. The BCM won't go to sleep if it sees some
>>> circuits still active, the most common of such circuits is the remote
>>> door locking system. Here's the rub, to make the BCM go to sleep you
>>> need to *lock the doors*. With the BCM active the parasitic draw will
>>> be somewhere between 50 milliamps and 100 milliamps. That's hefty and
>>> will flatten the battery over a time span of a month or two or, at
>>> the very least, not leave enough charge to allow the engine to start.
>>> Remember, the ECM wants to see a *minimum* voltage in the battery and
>>> if it isn't there, it won't allow an engine start. Ah, the joys of
>>> "intelligent" systems!
>>>
>>> A lot of cars have a BCM that needs to go to sleep and the fitting of
>>> aftermarket accessories can result in the BCM not going to sleep even
>>> when the doors are locked. I prefer to leave my car unlocked whilst
>>> it is in the garage. I just take the keys out and plant them
>>> somewhere safe. But then, my car is a daily driver. I think the
>>> maximum it has sat without a start has been a week. But I have an
>>> intelligent charger that has trickle and float modes so, were I to
>>> leave my car idle for an extended stay, say a month or more, then I
>>> would simply plug the charger on to the battery. Not so doable
>>> however if you are leaving the car in, say, an airport long term car
>>> park. But then, you'd most certainly have the car locked - and
>>> there's always the RACQ.
>>
>> Forgot to add, the Mazda 3, if I'm not mistaken, has that start/stop
>> bullshit and, as such, is equipped with an AGM 60AH or 65AH battery. A
>> battery of that size, if in good nick, should be more than adequate to
>> deal with a nominal 10 milliamp parasitic drain over a few weeks. Just
>> do the math! Keith should just lock the doors, leave the battery
>> connected, and just enjoy his time away. Stressing over nothing!
>>
>>
>
> seems hard to believe any modern car would have a flat battery after
> just five weeks of sitting idle
>

More likely with modern cars.

--
keith on the 7 Oct 2021 wrote;
"He asserts that the claim is true, so, if
it is unproven, he is lying."

On 2/8/2022 10:09 pm, Clocky wrote:
> On 2/08/2022 9:59 am, Yosemite Sam wrote:
>> On 1/08/2022 8:30 pm, Xeno wrote:
>>> On 1/8/2022 8:09 pm, Xeno wrote:
>>>> On 1/8/2022 7:35 pm, Yosemite Sam wrote:
>>>>> On 1/08/2022 5:50 pm, Xeno wrote:
>>>>>> On 1/8/2022 4:54 pm, keithr0 wrote:
>>>>>>> Later this month I'm going away for about 5 weeks. I will just
>>>>>>> disconnect the battery on the MX-5, but I'm not sure about the
>>>>>>> Mazda 3. If I just leave it, there is a good chance that it will
>>>>>>> be pretty flat when I get back, but it's undesirable to
>>>>>>> disconnect it with all the electronic gubbins on it. Any opinions
>>>>>>> about leaving it on a trickle charger?
>>>>>>
>>>>>> It's what I would do. Get an intelligent charger that does trickle
>>>>>> and float for best results.
>>>>>>
>>>>>> BTW, does it have *that much* idle current draw on it? My mate
>>>>>> leaves his Prius for a couple of months at a time with no real
>>>>>> issues.
>>>>>>
>>>>>
>>>>> I wouldn't think it's necessary to disconnect a battery just
>>>>> because it's not being driven for five weeks.
>>>>>
>>>>>
>>>> Normally not but parasitic draw is the $64 question in play here.
>>>> Some cars have more than others and that will determine the ability
>>>> to restart the car on return. Given the vintage of the MX-5 in
>>>> question, I would expect a parasitic drain on the battery to be
>>>> about 20 milliamps. Any great deal more than 20 milliamps and the
>>>> battery may well not last the distance.
>>>>
>>>> With the Mazda 3, on the other hand, life gets a little more
>>>> complex. The parasitic drain on the 3 is notionally 10 milliamps.
>>>> The caveat is that it will only be 10 milliamps *if* the Body
>>>> Control Module (BCM) goes to sleep. The BCM won't go to sleep if it
>>>> sees some circuits still active, the most common of such circuits is
>>>> the remote door locking system. Here's the rub, to make the BCM go
>>>> to sleep you need to *lock the doors*. With the BCM active the
>>>> parasitic draw will be somewhere between 50 milliamps and 100
>>>> milliamps. That's hefty and will flatten the battery over a time
>>>> span of a month or two or, at the very least, not leave enough
>>>> charge to allow the engine to start. Remember, the ECM wants to see
>>>> a *minimum* voltage in the battery and if it isn't there, it won't
>>>> allow an engine start. Ah, the joys of "intelligent" systems!
>>>>
>>>> A lot of cars have a BCM that needs to go to sleep and the fitting
>>>> of aftermarket accessories can result in the BCM not going to sleep
>>>> even when the doors are locked. I prefer to leave my car unlocked
>>>> whilst it is in the garage. I just take the keys out and plant them
>>>> somewhere safe. But then, my car is a daily driver. I think the
>>>> maximum it has sat without a start has been a week. But I have an
>>>> intelligent charger that has trickle and float modes so, were I to
>>>> leave my car idle for an extended stay, say a month or more, then I
>>>> would simply plug the charger on to the battery. Not so doable
>>>> however if you are leaving the car in, say, an airport long term car
>>>> park. But then, you'd most certainly have the car locked - and
>>>> there's always the RACQ.
>>>
>>> Forgot to add, the Mazda 3, if I'm not mistaken, has that start/stop
>>> bullshit and, as such, is equipped with an AGM 60AH or 65AH battery.
>>> A battery of that size, if in good nick, should be more than adequate
>>> to deal with a nominal 10 milliamp parasitic drain over a few weeks.
>>> Just do the math! Keith should just lock the doors, leave the battery
>>> connected, and just enjoy his time away. Stressing over nothing!
>>>
>>>
>>
>> seems hard to believe any modern car would have a flat battery after
>> just five weeks of sitting idle
>>
>
>
> More likely with modern cars.
>
For sure, and the reason being way too many points of failure. The BCM,
for instance, controls such body items as power windows, power mirrors,
power door locks, remote locking, climate control, immobilisers, alarms,
and so many more. A fault in any one of these can prevent the BCM from
going into sleep mode yet might not ever raise a fault code. One thing
you might find surprising under the list of devices the BCM controls is
the *fuel pump*. You would wonder why that is not controlled by the ECM
and you would find that the fuel pump *is controlled* by the ECM. The
BCM however has an override control on the fuel pump. The security
system, in the case of an attempted car theft, hotwiring or the like,
alerts the BCM and the BCM then turns the pump off. Faults in the
security system can trigger the same response. Fault diagnosis on such a
scenario can be a real bitch. Good luck working it out without an
extensive knowledge of the system and, most importantly, access to the
full wiring diagram(s).

--
Xeno

Nothing astonishes Noddy so much as common sense and plain dealing.
(with apologies to Ralph Waldo Emerson)