Power Meter: Accurate Electricity Measurement

Hi,

Okay, the Audi A3 station wagon with a 2.0 FSI engine had been sitting for 2 weeks, and then the battery was dead.
Since I wasn't sure if this was normal or if the battery was supposed to last longer, I measured the car's quiescent current.
Okay, here's my problem. I disconnected the battery and connected a measuring device. However, the CAN bus isn't going to sleep (the warning light button is illuminated and won't turn off). I even waited for 2 hours, but nothing happened. The current consumption was then between 0.6 and 1 Ampere, which is normal if some control units are running.

If the measuring device isn't connected, the light will turn off after about 10 minutes.

Does anyone know what might be wrong, because I would like to measure the actual power consumption!
It probably isn't the measuring device itself, because it works perfectly fine otherwise, but what else could it be? Without the measuring device, the power consumption is definitely not that high, otherwise the battery would never last for 2 weeks!

I am grateful for any advice!

Best regards,

Hi,

If the power meter is properly connected and functioning correctly, it should not affect the operation of the control unit. I suspect that you may have the meter set up incorrectly in some way; it may not be able to measure the required current, or you may have connected it to the wrong place.
Do you know how to measure electricity?
http://de.wikipedia.org/wiki/Amperemeter

Best regards, Rainer.

HI,

Is it not possible to put the vehicle into "transport mode" if there is a planned period of inactivity?

Or is it only possible for the first xyz kilometers?

m;

What is the internal resistance of the measuring device? It may have affected the control units. Did you use proper terminals to connect the device?
You could short-circuit the measurement leads at the measuring instrument, and once the bus is quiet, you can remove the short-circuit and read the measurement value.

Hi,

Thank you for the tips.

Yes, I'm familiar with measuring electricity and related things. I learned about it at some point.
That's why I find what's happening there so strange!
Okay, I'm going to use a different measuring device for this case and see what results I get!

If you happen to have an RNS-E system, you might not have waited long enough... they remain active for up to 2 hours and 15 minutes. Also, there are software updates available for navigation systems that consume a lot of power.

Another potential source of error is the brake light switch. This is also often the cause of increased idle current. Optimized versions were installed from 07/2005 onwards.

Okay, so it doesn't have a navigation system. It just has the Concert II radio. And the car was purchased in March 2006.