Battery Drain issue

[smokum]

just wondering Wuffer how fast does this drain runn down the batteries?

[Wuffer]

Quicker than overnight... and they are new MTP 93 batteries....

[smokum]

Well since i had a kind of the same issue, with my seats for some reason using power i tested for amps.
dont know if that helps it could be 12v but .5 amps or 12v and 10 amps.
Just tossing it out there
With the key off ofcourse

[TxGR8White]

I may have found the culprit. I just got off the phone with Wuffer and it seems to work for him too. I am waiting to see if in a real-world setting it does work properly. So far, it does. I will report back later.

[Quackers]

Are you keeping us in suspense?

[TxGR8White]

Are you keeping us in suspense?

No, I do not want to give false hope, nor do I want there to be problems with other cars until I determine that this course is correct.

[Quackers]

I understand. Very thorough! I hope it's successful for all

[Imndeep]

Wuffer, TxGr8White, I love you guys. I've been trying to figure this out since I've owned my car.

[Wuffer]

Will report back tomorrow. I have removed the battery tender, measured the voltage at the +/- posts under the hood at 3:30 this pm. Will check voltage in the am and again 24 hours after removing the tender. I can report that the water valve solenoids are no longer getting hot. Cautiously optimistic...

[revtor]

Revtor/Steffen - here are this mornings updates based on your requests:
Voltage at Pin 8, key off: 0v
Voltage at Pin 8 key in Position II: 12+V

This confirms pin 8 is connected to the ignition switch. Thus the electrical troubleshooting manual (ETM) is correct and this also proves nothing is wrong with the ignition switch.

Key in Pos II, press Timer button: Ventilation Off
So it appears That US spec cars of 93 have Park Ventilation Standard?

Yes, I think it's now quite safe to assume this was a standard feature on US E31. We really should make a list of standard equipment because the build sheets are worthless in these situations...

Anyway, the problem remains: pin 7 is always hot while it shouldn't. Something is wrong with the park ventilation system.

TxGR8White and Wuffer now have a work-around. It does not fix the problem, but at least it will stop the park ventilation system from draining the batteries...

[quest]

Probably electronic system in the module, maybe capacitors ? Park Ventilation module is somewhere behind the glove box.

[TxGR8White]

A15 Module is faulty.
You have three options here:
1) replace the A15 module (takes less than 5 Wuffer minutes)
2) replace the K4 relay with a K1 relay
3) cut off the 86b leg from the K4 relay (drastic I know, but it works).

[revtor]

Or

4) Disconnect the A15 park heating/ventilation module behind the glove box (accessible by removing the lower dashboard cover).

Note that options 2, 3 and 4 make you lose park ventilation entirely, but it was already broken to begin with... The real fix is repairing or replacing the A15 park heating/ventilation module, but if you don't care about park ventilation these are quick workarounds to stop the battery drain issue.

[Wuffer]

After PM's and telephone calls from Revtor and TxGR8White, last nite and this morning, I replaced A15 (had 5 of these little guys on my shelf) on the offending vehicle. result - no longer have unwanted voltage at Pin 7 of K4 and neither K4 or the water valve heats up with key off any longer. I agree with Tx and Revtor that A15 is the culprit and further diagnosis of the module is required. Module disassembly revealed 2 capacitors on the board which may cause the faults experienced by myself, Tx and inDeep.
Collaboration between the three of us resulted in determining the root cause of three similar, yet different issues. This is a true indication of how the collective knowledge of passionate E31 owners on this forum can resolve problems.

[Ahmed303]

After PM's and telephone calls from Revtor and TxGR8White, last nite and this morning, I replaced A15 (had 5 of these little guys on my shelf) on the offending vehicle. result - no longer have unwanted voltage at Pin 7 of K4 and neither K4 or the water valve heats up with key off any longer. I agree with Tx and Revtor that A15 is the culprit and further diagnosis of the module is required. Module disassembly revealed 2 capacitors on the board which may cause the faults experienced by myself, Tx and inDeep.
Collaboration between the three of us resulted in determining the root cause of three similar, yet different issues. This is a true indication of how the collective knowledge of passionate E31 owners on this forum can resolve problems.

Wuffer.....since you have 5 of these, would you sell a couple?

[Wuffer]

Yeah - but you dont even have an 8 Faisal! 8-)

[Ahmed303]

Yeah - but you dont even have an 8 Faisal! 8-)

Never too late to stock up on Parts...

I am looking at a couple and negotiating the $$ with my Budget Officer (My better half). Hopefully soon. I want to have my 8 before the Yearly DC Metro E31 Fall Drive.

[Wuffer]

Got a couple of really nice 91 low mileage Calypso Red/Black Canadian Spec cars available out here - including one with sport seats! One car has 94K kms the other (with the sport seats) 68k kms... Road trip??

[Ahmed303]

Thanks Wuffer. But you know me. I am not really a Calypso guy. I am holding out for a Silver, Blue or Diamond Black.

[smokum]

After PM's and telephone calls from Revtor and TxGR8White, last nite and this morning, I replaced A15 (had 5 of these little guys on my shelf) on the offending vehicle. result - no longer have unwanted voltage at Pin 7 of K4 and neither K4 or the water valve heats up with key off any longer. I agree with Tx and Revtor that A15 is the culprit and further diagnosis of the module is required. Module disassembly revealed 2 capacitors on the board which may cause the faults experienced by myself, Tx and inDeep.
Collaboration between the three of us resulted in determining the root cause of three similar, yet different issues. This is a true indication of how the collective knowledge of passionate E31 owners on this forum can resolve problems.

ACK imagine what the dealerships went thru to try to narrow down what gremlins our cars had...Then what it cost the customer?

Thanks Wuffer. But you know me. I am not really a Calypso guy. I am holding out for a Silver, Blue or Diamond Black.

What ever happened to the aston martin thing???
Or was that someone else?

[moutine]

That is most likely GenMod failure...

Hey Greg... Just diagnozed and found that those two green relays in trunk are hot eaven car has sat all day. So this points to GM failure? And replacing capasitors could fix this battery drain issue?

[TxGR8White]

Hey Greg... Just diagnozed and found that those two green relays in trunk are hot eaven car has sat all day. So this points to GM failure? And replacing capasitors could fix this battery drain issue?

Not Greg...
..Correct - GenMod failure at the capacitors.

[moutine]

Not Greg...
..Correct - GenMod failure at the capacitors.

Sorry misunderstanding but thanks anyway. Just ordered set of caps and going to report next week what happened.

[RAFFEAL]

i have the same drain thing happening after three day won't start too but my lights stay on after i turn off the car, so i just took out the two 7.5 fuse 10 & 11 in the front driver side box under the hood and the light stay off after car switch off now but only one head light works now the driver side but both lights in bumper work

where is a15 and k4 i got an photo and i do see these two do any of you have an photo so i can replace these two relays thank you

ok i know where the a15 is but my car is from japan so all this won't work for me or will it

[Wuffer]

K4 is the yellow relay in the back row far left in the front E-box. Get yourself a copy of the ETM from my site - tells you where everything is.... You J-spec car is no different than any other 90/91 E31 in this regard.