andrzej19

Hi.
Two days ago in my car has gone the battery. I'm a little surprised, because the car is from the year 2011.
After buying a new battery I checked quiescent current of the vehicle.
On the start, the value of the current was about 4 A, and after about 10 minutes, fell to 0.41 A.
Whether the current 0 .41 A is normal?
It's already time to look for a device that "steals" power, and if so, where to start ?
Cheers Andrew

Moviela

Many modules in the car consume current to listen to the CANbus. There comes a point when this is no longer productive as the bus itself has gone quiet.

410 mA is too much. At rest the car should draw 50 to 100 mA, depending on individual devices and temperature.

The first place to look is the obvious culprits, a glove box or trunk lamp.

It might be cheaper to simply ask a dealer to chase the trouble because they have the tools to do that without causing more damage.

andrzej19

Thank you for Your reply.
However, I wonder that, according to various opinion - older cars (without CAN) and later (with CAN) have the same power consumption. (50 mA - 100 mA). I think that these values ​​should be different.
Am I right?

Moviela

Older cars had electronics that drew that amount, mostly engine controls and entertainment systems.

Modern cars with CAN (controller area network) turn the transceiver on and off. When awake LED's in each device draw about 20 mA. When all are asleep they each draw micro amps while listening for a signal. That is why old and new cars draw about the same amount when switched off.

Some modules develop a problem that does not allow sleep, and just like noisy neighbors, they keep everyone else "awake."

You can disconnect different modules to find out who is the bad actor. Problem is they are located all over the car. Some require considerable time to expose using this technique, whereas a dealer can use his online tools to point to the bad boy.

andrzej19

Thank you for your help - tomorrow I start searching for the cause of the problem.

andrzej19

Problem solved - it is to maintain the navigation system is drawing too much current. After the repair, the current drawn by the vehicle is 40 mA.
Thank you for your help.

audi8k

How did you manage and what method did you use to isolate the problem?