1989 928 Memory seat battery drain
05-01-2015, 06:50 PM
#1
Nordschleife Master
Thread Starter
1989 928 Memory seat battery drain
Hello Gents,
I am working on an 89 928 S4.
The car has a battery drain of 0.11-0.12 which is higher than I like.
The drain drops right down to .01-.02 the moment that you remove fuse 20.
Unplugging the drivers seat removes the drain as well.
Unplugging pin 2 on the memory controller under the dash kills the drain as well.
The drain is coming from seat controller board connector 9, pin 3 (30)
Then goes through the 14 pin seat plug pin 14.
Which goes to plug 2, pin 3 on the memory controller under the dash (by ABS brain).
The wire is Red/white, notated as 30. Indicating it should be +12V hot at all times.
This leads me to believe that the memory controller (92816813600) is likely suspect. As I can leave the seat plugged in, and disconnect only this brain, and the drain disappears which appears to be the termination of the circuit.
I'm curious if anyone here has run in to this in the past, or if anyone can see a fault in the logic on this. Hopefully prior to ordering a new memory module....
I am working on an 89 928 S4.
The car has a battery drain of 0.11-0.12 which is higher than I like.
The drain drops right down to .01-.02 the moment that you remove fuse 20.
Unplugging the drivers seat removes the drain as well.
Unplugging pin 2 on the memory controller under the dash kills the drain as well.
The drain is coming from seat controller board connector 9, pin 3 (30)
Then goes through the 14 pin seat plug pin 14.
Which goes to plug 2, pin 3 on the memory controller under the dash (by ABS brain).
The wire is Red/white, notated as 30. Indicating it should be +12V hot at all times.
This leads me to believe that the memory controller (92816813600) is likely suspect. As I can leave the seat plugged in, and disconnect only this brain, and the drain disappears which appears to be the termination of the circuit.
I'm curious if anyone here has run in to this in the past, or if anyone can see a fault in the logic on this. Hopefully prior to ordering a new memory module....
05-01-2015, 07:54 PM
#2
Rennlist Member
Few years back, I helped one local fellow troubleshoot what looks like identical problem. His was an '88 S4, 5spd. Attached pics show what I reported to him and we've agreed to leave the #9 conn. off, at that time. I left it up to him whether he wanted to pursue getting the board repaired or get a new one. I think they were running around $400 new, back then. I haven't been in touch with him since. Hope this is of some value.
05-01-2015, 09:03 PM
#3
Nordschleife Master
Thread Starter
The problem is the drain I do not believe to be with the seat.
The memory controller sits near the ABS brain.
If I unplug all connectors but pin 2, the drain is present. The moment I remove that 1 wire from that connector, the drain disappears.
Given that, I believe it to be with the mirror controller brain.
But if that wire is left disconnected, then the mirrors do not work at all.....
That brain appears to be around $340 on pelican. But I'm thinking about just changing that wire to a 15 circuit. Might cost us the memory feature, but should leave all other functionality intact.......
The memory controller sits near the ABS brain.
If I unplug all connectors but pin 2, the drain is present. The moment I remove that 1 wire from that connector, the drain disappears.
Given that, I believe it to be with the mirror controller brain.
But if that wire is left disconnected, then the mirrors do not work at all.....
That brain appears to be around $340 on pelican. But I'm thinking about just changing that wire to a 15 circuit. Might cost us the memory feature, but should leave all other functionality intact.......