12v battery maintenance, issues, etc.

[Roy124]

49 minutes ago, Mojo1010 said:

assuming the high of 12.8v reading it had previously after similar usage. Today it measured 12.07, so down 0.73v, 50% down according to the charts. 

At what point after that previous journey did it give 12.8v?

[Cyker]

1 hour ago, Max_Headroom said:

Thanks for the figures is that for the hybrid or ICE?

I asked at what voltage the 12v battery will fail to start the hybrid cars as the battery  only powers the 12v system there is no cranking involved so again my question is do any owners know how low their battery voltage dropped before it failed to start the hybrid?

 

That's really hard to answer as it isn't as simple as that - Voltage is only an approximate and indirect way of measuring the Battery health and capacity.

You could have 2 similar batteries - One at 11.7v and the other at 12.4v, only to find the 12.4v one sags to 6v as soon as a load is put on it, while the 11.7v one barely sags and starts the car fine.

That's why we often tell people, if they get the Battery tested, they have to make sure it's tested under load - Just jamming some multi-meter probes on the terminals and seeing it shows 12v doesn't actually mean anything if the Battery is unloaded.

I'm not sure what the tolerance of the car's computers is, but from what I remember car electronics are normally rated for 9-16v tolerance

[Mojo1010]

15 minutes ago, Roy124 said:

At what point after that previous journey did it give 12.8v?

After using car for 3hrs. 

[Chas G]

3 hours ago, Cyker said:

That's really hard to answer as it isn't as simple as that - Voltage is only an approximate and indirect way of measuring the battery health and capacity.

You could have 2 similar batteries - One at 11.7v and the other at 12.4v, only to find the 12.4v one sags to 6v as soon as a load is put on it, while the 11.7v one barely sags and starts the car fine.

That's why we often tell people, if they get the battery tested, they have to make sure it's tested under load - Just jamming some multi-meter probes on the terminals and seeing it shows 12v doesn't actually mean anything if the battery is unloaded.

I'm not sure what the tolerance of the car's computers is, but from what I remember car electronics are normally rated for 9-16v tolerance

Toyota advice is to turn the headlights on for x minutes and then check the voltage. If its +12 volts everything in the garden is Rosie.

[Dala]

2 hours ago, Chas G said:

Toyota advice is to turn the headlights on for x minutes and then check the voltage. If its +12 volts everything in the garden is Rosie.

Voltage at 20 °C:

12.0V or higher
(Turn off the POWER switch and turn on the remote headlights for 30 seconds.)

[Derek.w]

You can consider this as a guide only.

11.8 volts or lower difficult to start.

10.8 volts Non starter 

[jthspace]

OK, a bit lighter (no pun intended) but here is a video of getting your Battery reconditioned

Battery reconditioning

[hind]

Wait, is this the Multi factory? 😄

PS it's a joke, Mutli lawyers please don't sue me 😛

[Jimota]

2 hours ago, jthspace said:

OK, a bit lighter (no pun intended) but here is a video of getting your battery reconditioned

Battery reconditioning

Think I’ll rummage through my old tool box to see if I still have a hammer and chisel.  I definitely have a wok.

[Dala]

17 hours ago, Max_Headroom said:

Thanks for the figures is that for the hybrid or ICE?

I asked at what voltage the 12v battery will fail to start the hybrid cars as the battery  only powers the 12v system there is no cranking involved so again my question is do any owners know how low their battery voltage dropped before it failed to start the hybrid?

 

April 2021 - for me 11.6V / 4°C , then followed a jump start

[Derek.w]

Has anyone considerded 12 volt Battery waranty it may be invalid if voltage drops to 12.05 or 12.1 volts!.

[Roy124]

On 1/27/2024 at 3:07 PM, Mojo1010 said:

After using car for 3hrs. 

Not the question I asked.  You stopped the car and switched off.  Did you measure the voltage immediately or after how long?

[haelewyn]

Is there a way to see the voltage constantly ? My toyotas never had a voltmeter.

Other than an obd tool, I can't think of much.

[hind]

56 minutes ago, Derek.w said:

Has anyone considerded 12 volt battery waranty it may be invalid if voltage drops to 12.05 or 12.1 volts!.

I didn't buy a Battery from Toyota. I bought a car. I am using it in a way considered to be regular. I am not required to measure the voltage, manual doesn't say that, so why would the warranty be void? 

[Dala]

It's a shame that the same logic cannot be applied to other accessories.  Wipers, tires, etc.

[hind]

Actually it can. It's just a matter of time and character of the degradation which distinguishes regular wear from manufacturer defect.

[Derek.w]

16 hours ago, haelewyn said:

Is there a way to see the voltage constantly ? My toyotas never had a voltmeter.

Other than an obd tool, I can't think of much.

You can buy bluetooth Battery monitors no need to be in the car, or use a standard multimeter on the correct range, ODB 2 readers but the cheapest maybe just one that plugs into the accessory port but this only shows you a voltage after opening the doors & going into acc mode or starting up the car so its only on for a second or two then its showing charging voltage if the car is running.

[haelewyn]

Thanks... I have a multimeter but wouldn't want to wear out the hinges of my bonnet. 

Gonna look for the cig lighter thingie and the bluetooth one.. didn't know they existed. 

[Mike1394]

I've only been let down by my Yaris three times, I know that I don't drive it enough but two of those three times happened when we were setting off for hospital appointments. My DBPower jump starter worked both times, thankfully. I had a Ctek charger tail and a BM2 Battery Monitor installed by my dealer (as an octogenarian I'm long past heaving seats about),  and after checking the Battery state compulsively for a couple of weeks I'm down to a quick check in the morning to see how things are. I can recommend the BM2, it's given me peace of mind, and the Ctek tail has lived in both my Prius and Auris. I'm a lot happier now than I was a month or two ago, and getting the bonnet up and the fuse box cover off during one of our recent storms proved to be a right faff. Be prepared . . . . .

[Dala]

2 hours ago, Mike1394 said:

I've only been let down by my Yaris three times, I know that I don't drive it enough but two of those three times happened when we were setting off for hospital appointments. My DBPower jump starter worked both times, thankfully. I had a Ctek charger tail and a BM2 Battery Monitor installed by my dealer (as an octogenarian I'm long past heaving seats about),  and after checking the battery state compulsively for a couple of weeks I'm down to a quick check in the morning to see how things are. I can recommend the BM2, it's given me peace of mind, and the Ctek tail has lived in both my Prius and Auris. I'm a lot happier now than I was a month or two ago, and getting the bonnet up and the fuse box cover off during one of our recent storms proved to be a right faff. Be prepared . . . . .

Hi, Mike
can you show some graphs from BM2?
Where did the voltage of the car Battery drop?

[Derek.w]

BM2 Battery monitor try typing it into s search engine.

 graph from BM2 device.   

 

[Derek.w]

Dont worry if voltage drops below the 12 volt line as its only a load voltage drop and recovers within a few seconds.

[anchorman]

I’m a qualified mechanic and I’m not the least bit worried about these Battery issues but all this measuring Battery voltage is a joke and not at all reasonable for anybody other than a fanatic.   It is reasonable to advise people to allow time for the Battery to charge but it isn’t reasonable to expect them to monitor and record it in this way.  I have a jump pack under the passenger seat but in normal use, I expect it to start every time.  We know the battery is the weak link so what good are these 85 pages of perpetual graphs and comparisons to decimal points of a volt?   Mutlu batteries are not up to the job.  

[Dala]

joke is : 

" I’m a qualified mechanic and I’m not the least bit worried about these battery " 

[hind]

49 minutes ago, anchorman said:

what good are these 85 pages of perpetual graphs and comparisons to decimal points of a volt?

Not sure about the others but for me that's really handy insight into the subject of power management in the car that I own so I can take actions and prevent Battery malfunction in the future.

I'm sure 99.9% of the Y4/YC owners who just drive don't visit this thread 🙂 but they often come to some stupid conclusions like "damn these Toyota hybrids, because of the Battery issues now I have to take a longer route to work to allow the Battery to charge properly, ecology my a$$"