I drive my 1998 VDP at least once a week, but had previously had battery discharge problems. Battery has been replaced, but yesterday after a week or so, the car was DEAD as a hammer. Battery had a 2.3V charge on it.
I know these super computer's use battery almost all the time, but how can I find the source of this vampire drain?

TIA

ap

 

Read some of the threads / youtube

I like mV across fuses.

 

two 15amp fuses are showing 1.0 and 1.4 mamp readings. The fuses are labled BPM. Any ideas?

 

go into the stickies and pull down the wiring diagram for your year: trace the wires from the BPM until you find the light that is on all the time (most likely).

Told the story many times about a Bavaria I had in Tokyo years ago: killing baaateree, daily. A Chief petty officer working in a unit nearby, had been trained by BMW in Germany when stationed there: "likely the switch to the trunk!" Today, you can test that with your smart phone, but I put my young son (now retired Navy helo pilot) in the trunk and told him not to be scared but knock when the light goes out: no knock, "light didn't go out." The spring loaded switch button had pressed a hole in the facia over the years so the switch was always on. A penny and tape; after three batteries and lots of hail marys for all the swearing!

 

The car will not POWER DOWN immediately but will take maybe 20 minutes to completely go into 'sleep-mode'.
The boot lid latch can be closed with the lid open to shut the lights off. (simulate boot lid closed)
Put an ammeter across the earth terminal and braided lead to watch the draw gradually go from 400+ ma to about 30 ma when the SCP network 'powers-down'.

The BPM is on the SCP network and the INSTPK might have a 'U' code (DTC for the network).

The BPM fuse should be in one of the HEELBOARD fuseboxes.

The car will not start without the BPM in the circuit so if the drain is found in the BPM circuit you cannot leave the fuse out.

 

The 1 amp drain is still not resolved for this 20 yr old issue, now the door locks seems to be actuating, only sound, buttons not going up and down. The interior lock/unlock button does not work at all, opening the driver side door from inside with handle does not unlock doors as before, and now the front passenger side window switch operates the passenger side REAR window. I can use the key from outside to lock or unlock the doors but it does not work as it should, using multiple turns to lock or unlock, with even the alarm coming on. Could it be a main door module? I replaced one a while ago, drivers side rear. tia

 

Every time the DRIVER's window switch operates the Right Rear window, the car needs a HARD RESET!

The door modules are CONFUSED and the networks are in need of REBOOT.

 

OK, I'll reboot. thanks

 

UPDATE: This 20 yr old current draw problem was still there, but I went for gas the other day and the fuel door would not open.
Can that actuator be a source of the draw? I had to physically move the pin to open the door.
I'm doing a draw test right now and it's showing zero to 1 milliamp with trunk light off.
tia

 

Make sure you read your owner's manual before you make life harder for yourself.

 

When you exit the vehicle and remove the key you trigger pin 4 to pin 5 of the ignition linier switch , this linier switch can stick

this startes the security system countdown and must satisfy certain agreements before going to sleep with a very low current sleep mode draw

one of those agreements is the steering coluum position

You can switch the column movement from auto to off and see how it does

In reading the fuse draw the trunk must be closed as this is one of the agreements