Current Consumption: Idle State of Control Units - ~30mA

The following problem:
Passat Variant V6 TDI AKN model 2002, battery 82Ah.

In February, after 14 days of inactivity, the battery was completely drained.
'I had it. The battery was charged, and I checked the acid density and voltage of all the cells; everything was fine. After a few weeks, there was another period of downtime, about 10 days, and the battery was almost completely discharged again.'
I once measured the power consumption of the vehicle in idle mode.
(Doors closed; old-fashioned radio turned on, etc.) approximately 0.03A.
For further troubleshooting, the value is not too high. The repair manual 'So wirds gemacht' states that the acceptable range is 1-3mA. However, this has been stated in every manual for at least 8 years. Before I check all the fuses,
To find the consumer, follow the chain of events. My question is: How much?
Power is normal. Oh, and I also had a raccoon or similar animal during that time.
Something like that happened in the car, but it only affected my hose from the pressure gauge. I didn't notice anything else.

Have fun measuring yourself. Or knowing.
Thank you in advance!!!!!!

School.

I found something while searching about faulty ABS/ESP control units.
'It doesn't switch to sleep mode,' read Michael II. 'But only with the Bora and Golf. Did this also happen with the Passat?'

School.

Hi.

For reference - I once measured the following on my tractor:
Interior lighting in "wide beam" mode: approximately 6.5 mA.
Dashboard (clock, etc.) approx. 1 mA.
Reverse leakage current of the alternator diodes: approximately 40 μA.

After interrupting these leakage current paths, no discharge current flowed at all.

Hello,

Radio installations and, in particular, hands-free systems are a common source of parasitic current drain. Some hands-free systems remain active with a relatively high idle current for up to half an hour.

Okay, let's do some calculations. 30mA multiplied by 1000 hours equals 30Ah. So, theoretically, a good 82Ah battery should still be able to start the car even after 30Ah have been drawn over 6 weeks.
Either your measurements are incorrect, or the battery has significantly less capacity than expected.

Best regards,
Christian.

Sure, no problem!

I don't have a hands-free system.
I've measured it several times, and it's always around 30mA (the multimeter shows...).
Adjust in steps of 10mA. Connect the ground wire to the battery and use a multimeter to measure.
Minus battery and vehicle ground = 0.03A.
I've also calculated using 2/3 of the battery capacity (55Ah * 12V): 0.36W (0.03A * 12V) = 1833 hours. So, it shouldn't be a problem.
But the battery is also only 1.5 years old.

School.

Schulle wrote:

Disconnect the mass from the battery and connect the multimeter between. Minus battery and vehicle ground = 0.03A. I've also calculated using 2/3 of the battery capacity (55Ah * 12V): 0.36W (0.03A * 12V) = 1833 hours. So, it shouldn't be a problem. But the battery is also only 1.5 years old.

Hi.

"This doesn't quite add up with the reported starting problems after only 10 days."

Perhaps you are "eliminating" a stronger consumer when you disconnect the ground wire, and thereby completely interrupting all current flow until it reaches the measurement?

Hold the measuring device against the battery terminals and the cable, while you disconnect the cable .

Hello,

Try pulling the fuses one by one until your current draw disappears. Then you'll be able to see where the power consumption is coming from.

hi!
I don't know exactly how you measured it, but it's also possible that the current could decrease further if you choose a longer measurement period. This is at least the case with vehicles that have the Mercedes-Benz star. The control units switch to standby/sleep mode in stages, sometimes not even after more than 30 minutes. Why don't you leave the multimeter connected overnight?
To my knowledge, the maximum permissible quiescent current for the current C-Class models is 20-25mA.
But according to the calculation, it seems there's another error somewhere else.

Best regards,
pretzelman01