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View Full Version : Help with parasitic draw - delays car's sleep.



driggett
03-03-2017, 06:32 PM
I am going to pick up my BMW 2014 335i from the dealer who put a new battery in and they informed me that I had a parasitic draw from my after market accessaries. They unplugged them from the fuse box and the problem was gone. I have a ALP with three heads. bluetooth, hifi and a stir plus as a separate unit with escort live module. The units are about 1.5 years old now. The BMW dealer tech said that they were delaying the car from going to sleep. Normal sleep time is 20 minutes but with these units in it was 45 minutes. They also saw when the car was shutoff a huge spike after 15 secs and then a slow downward draw for 45 minutes. I am going to take it back to the electronics installer but wanted to see if anybody had any suggestions. When I brought the car in all 3rd party units were functional.
Thanks,
Chris

Tman
03-03-2017, 08:12 PM
I cannot give a diagnostic , though what i would do to definitively stop any draw :
i would use a main switch to deliver the ground to all the after market accs = no close circuit = no draw.

Good luck.

The way to see any ghost sucker is to disconnect the positive , hook a meter in amps mode preferably in milliamps , reconnect the positive , check the reading over 1/2 hour.
I suspect more the car than the accessories , you can repeat the process shutting off your after market accessories.

radargeek
03-03-2017, 10:21 PM
You need to find a circuit that cuts off completely when you shut the ignition off, and connect your CMs to that.

The circuit it's on now apparently has draw sensing on it which keeps it powered on for longer when there's a load on the circuit.