Schon die 3te Batterie - immer das gleiche Problem | Posts 16+

Hi,

Let's go back to the battery voltages:
A fully charged lead-acid battery typically has a voltage of around 12.6 V after some rest. Below 12.4 V, the state of charge is no longer optimal, and at 12.04 V without a load, the battery is practically completely discharged.

If you measure 830 mA, the quiescent current of the discharged battery is the cause. Disconnect the fuses one by one and observe the quiescent current. Hopefully, you will find the culprit soon.

Hi,

I also had an interesting battery-related story yesterday/today.

My parents' Passat 3BG 1.8T (02/01, 20,000 km) has been exhibiting "strange things" lately, such as the check engine light flashing, etc. So, during Easter, I took my laptop to connect VAGCOM and check the diagnostics.

Since I don't have a working battery and (still) no working 12->230->laptop power supply, I took the opportunity (since there's no power at the parking spot) to read out my Ibi again - of course, everything was okay .

"I found several errors in the Passat log, which I initially just copied to identify a pattern, because the messages, especially when they occur frequently, are often the result of a common cause."

The comfort control unit reported some undervoltage issues, as did the seat control unit, so I went back to the main system gateway (MSG), which displays the voltage in one of its measurement blocks.

I was shocked to see that the voltage was only 6.5 volts! It's amazing that anything still works with such a low voltage.

Naturally, it was no longer possible to start the engine. Also, VAGCOM could only be used for a few seconds before it also stopped working.

The day before, we drove the car 50 km, and my parents had also used it the week before, so it had already been charged. It always started before (there were never any problems), although usually on the first compression stroke, which is still possible even with weak batteries. It seems that the 5 minutes of cranking with VAGCOM finally drained the battery.

We then removed the battery - after charging it overnight, it had 11.95 volts, which already dropped noticeably under an 8-watt load -> completely useless, and that after just under 3 years.

However, and now comes the absolutely incomprehensible part: The car has a 1.8T engine, and comes with quite a lot of features, including xenon headlights, heated seats, and other power-hungry components (a radio with a TIM function), and yet, in that huge battery compartment, there's a tiny 44 Ah battery (original). I have absolutely no idea what the purpose of that is.

"Anyway, a 70 Ah battery is going in there now... that should solve the problem."

In connection with this, I came across TIM, which is a function in modern radios that saves traffic information even when the radio is turned off. This consumes a significant amount of power and may have contributed to draining the battery in this particular device. Perhaps the same issue is occurring in the car of the original poster... TIM can be turned off or adjusted in terms of the time it operates.

Best regards,

Jan.

Okay, so my radio doesn't have TIM. And I haven't swapped the ignition power and constant power connections either. And while it does remember the radio stations, it doesn't remember the track position of the changer.

Okay, here's the translation:

'I'm at the point where I disconnected the car battery on Thursday afternoon, including the radio and CD changer. Today, around midday, about 4 days later, I tried to start the car again: No problem. There were no signs that it was difficult to start. So, it's probably related to the radio or the CD changer.'

'So, I connected my friend's CD changer to her radio, which happens to be the same model as mine, and the track memory problem disappeared on her side, and then reappeared on my side when I connected my CD changer to hers. So, it seems the CD changer is the culprit in this regard. Now I'm going to test whether her Twingo, with its 44Ah standard battery, can last for 3 days. If not, it's likely due to the CD changer drawing power intermittently.'

Regarding the quiescent current: So, I measured a quiescent current of 45mA with the radio disconnected. I'm not entirely sure about the reading, but I once measured a Twingo, which has very little equipment besides the added radio, and the device showed a reading of 016. However, the Twingo, with its 44Ah starter battery, can easily stand for 2 weeks and start immediately. So, I assume it's 16mA and not 160mA.

Would 45mA be acceptable for my Golf? Because replacing the fuses didn't solve the problem, except for the fuse for the instrument lighting - in that case, the current dropped back to around 25mA.

Well, maybe I'll leave my Golf parked for another week after the Twingo test and then see how it goes. Otherwise, could you give me some advice?

Best regards,
VipViper2000

@Jan6k:

Don't worry about it, my dad's car battery also died over the weekend. His C200K, which is a gasoline-powered car, has a 100Ah battery, and it completely died - after exactly 3 years. Actually, this isn't the first time: His previous E-Class also had a 100Ah Hoppecke battery, which also failed after exactly three years. In my Golf II, it also lasted about 3 years. It's quite strange, although I've also had batteries that lasted over 9 years... It seems like some cars just have that problem.

@VipViper:

"45 mA is probably still within acceptable limits, I think. But that measurement was taken without the radio and DJ running... What was the value WITH the radio and DJ?"

'Yes, 45 cars were without a radio and CD player. In the cars that did have them, the numbers were between (!!) 90 and 160. It kept fluctuating somehow. But if I take the car to VW and they measure it and tell me that the quiescent current is okay, then it should actually be correct. Because they've said that now for the second time! I've been there a few times already because of the same problem.'

This morning, I tried to start my car, and I had the impression that it started better than it did when the old changer was still installed. I mean, it might actually have been the changer that was causing the problem, and now the battery isn't being drained as quickly.

But I'll figure it out. It's just a matter of time. It's just annoying when you have a bug that doesn't always occur. You know what I mean .

VipViper2000

Have you tried it with all the different settings/configurations?

Okay, so she didn't have them all outside at the same time. Because when I pulled most of the circuit breakers, there was never even a jump of 1 mA.

Best regards,
VipViper2000

Okay, a quick note about the TIM function: According to the description, the tuner only stays on if you press the TIM button after turning off the ignition. I tried this once with my MFD. If you don't press the button, the last message displayed while driving remains visible... so, the TIM function only draws power when it's intentionally activated, right?

@matthiasTDI96:

With my Delta, for example, you can set the TIM (Traffic Information Management) times. There are two settings available, one for the commute to work and one for the return trip. As far as I know, the device starts receiving information 30 minutes beforehand and remains active for a certain time after the set time (a total of 2 hours per set time). A similar configuration could be conceivable for the radio from VipViper (even with default time settings?).

"However, I don't think the maximum current of 160 mA will drain the battery too quickly."

Okay, my radio definitely doesn't have a TIM function. I don't even have a button for it, and there's nothing you can change in the settings related to that either.

Sure, at 160mA, the battery should last significantly longer than 3 days. That's why I'm also a bit confused. But maybe the changer is really defective. Interestingly, after any amount of idle time, it almost always gets stuck at CD 1, track 7 - and that's probably only because it's a (bad) copy and has an error at that point. It's conceivable that the changer simply continues running even when the ignition is turned off.

Okay, just a moment, now that I'm thinking about it, that could actually be it. Because if I'm on track 3 and come back after an hour, it doesn't start again at 1, but at 4 or something (I'm not entirely sure about that). Then, with a longer idle time, it continues until it reaches the song with the error. And that drains the battery. That might also explain why I'm not getting such high currents when I measure: Because when I disconnect the battery terminals, the changer stops running, and I don't notice it. But if I just turn off the ignition and leave the car, it keeps running. Well, it sounds plausible to me now. I'll see tomorrow if the Twingo is dead.

If it really is the exchange machine, this is probably the first time someone has experienced this problem. After all, who would blame the exchange machine?

Best regards,
VipViper2000

Hi,

You can easily test this theory.

Disconnect the fuse, connect the measuring device, set it to the highest A-range, and then turn on the CD player. Listen for a short time and then turn it off. If your theory is correct, the power consumption should be significant.

But don't overthink it - my VW CD changer in the SeaT Sound System 2 also continues exactly where you left off, even after turning it off, even in the middle of a song. To make it start from the beginning, you either have to select CD1 or remove and reinsert the magazine.

Best regards,

Jan.

- My VW changer in the SeaT Sound System 2 also continues exactly where you left off, even after being turned off - even in the middle of a song.

The problem is precisely that: My new 6-disc changer doesn't do that at all! I'll try to start the Twingo tomorrow. Otherwise, I'll see if I can figure out whether the changer continues to run after being turned off.

Best regards,
VipViper2000

Yay!!!!

Problem solved! It really was the changer! I tried starting the Twingo earlier just to test it, but the battery was so dead that it wouldn't even crank. That stupid changer is going back to the manufacturer tomorrow.

I was so annoyed about that thing earlier.

Thank you for your cooperation!

Best regards,
VipViper2000

Hello VipViper2000,

Quote:

At VW, they said the idle current was okay, so they've already replaced the battery for me three times.

That still leaves the question open: why couldn't your workshop identify this simple error? Is 160mA (830mA?) of idle current normal for them?

Best regards,

Is 160mA (or 830mA?) of quiescent current approximately normal for those?

Well, you're not allowed to ask me that. Anyway, the problem is solved now!

Best regards,
VipViper2000