Flott Leben

Okay, I've done some searches on battery/current drain and performed the ammeter test. I hooked up the meter between the ground strap and ground and then disconnected the battery ground. Then I pulled each fuse and each relay individually on the fuse/relay board in the passenger footwell. This is what I found:

1) Before I open the door: 170 mA drain (windows motors still charged)
2) After I open the door and the lights go off: 100mA drain (window motors no longer charged)
3) After I pulled all the fuses and relays one at a time, I found the aftermarket Clifford alarm (I think) was pulling about 15mA, so now I am down to about 85mA drain
4) If I then break the circuit (disconnect the battery entirely) and reconnect it I get a 20mA drain

So, I'm stil looking for some kind of 65 mA drain.

Few questions: first, which fuse is the digital clock on (I didn't notice it cut out when I pulled fuses)?

More importantly, is something remaining charged until the battery circuit is disconnected? Am I missing a relay or motor somewhere? (Note: my car does have an Alpine cellphone (disconnected) and the factory installed radar detector (still connected).

Thanks!

Bill Ball

We found a power window relay that was "latching" on power up and would stay latched on power off until the battery was disconnected. It was served by the power window fuse, so pulling that fuse was the clue that the problem was in that circuit.

However, you pulled ALL the central panel fuses and still have a current draw until you break the battery power. That points to a circuit that has an independent fuse or is unfused. It still may pass through the panel. Dave Anderson did a trick of pulling the central panel lower connectors until the drain went away. Then we mocked up jumpers for the wires on that connector, repowered, unpowered and pulled the wires one at a time until we found the culprit circuit.

Alan

Disconnect everything connected to the battery positive except the big fat 35mm^2 starter cable.

If you have stuff that you think is disconnected or should be disconnected - make sure its really out!

I would have expected the window controller relay to be pulling more than the ~70mA you quote in its on mode -> off mode...?

Since you quoted that power dropped to 20mA (~about right) when you disconnected - all you did was break a circuit - all the same stuff is connected... sure sounds like a relay still latched on... Coil current is usually in the 150ma range for automotive relays for switching - sustaining when already switched usually needs a little less...

Did you pull the window controller relay? any effect?

Alan

Flott Leben

Bill,
Thanks for the advice. That procedure sounds time consuming and I will keep it in mind if I can't find the drain. What other relays am I missing besides the ones directly plugged into the relay board: I through XXV (and one black Bosch relay with its own plastic holder floating above the relay/fuse board in the tangle of wires - either for the phone or radar detector, I believe)?

Alan,
That 170mA was what the current was drawing after the engine was shut down and before I opened the door, not while actually rolling up or down the windows - just static current. After I opened the door it dropped 70mA to 100mA. Then another 15 mA from pulling a 5A fuse I think was for the Clifford alarm (again floating in the tangle of wires above the relay/fuse board) - bringing me down to 85mA, then to 20mA after battery disconnect. You're right, it sure sounds like a latching relay to me but which one? I pulled each one individually and no drop.

Alan

Yes I understood the window relay measurement but these results still sound off...

Well its not just any relay - its one that is designed to self-latch because others fail by sticking the contacts on - not their own coil - current would be much higher in these cases...

That means candidates are Interior Light Delay relay (if delay fails on) - but lights would stay on too (did you pull the fuse to disable them all - does not affect the relay - does the delay normally work correctly). Window/Sunroof Control Relay has the door turn off and Defrost relay has a time delayed off. All of these are on the Central Electric panel. The seat heating relays have a timer operating period -(under the Dr. seat - but don't think you have this though...)

Does the alarm have any after-market additions for window roll-up or similar? these may be powered seperately? Still remove all the extra junk hanging off the battery +ve post...

Test the current again to be sure - focus on these relays (and any other additions you may find). Make sure the doors are closed when you test - and the hatch light switch connector is disconnected...

Your 20mA is about what it should be (10-15mA would be perfect..)

Alan

Fabio421

An alternator can retain a field or back feed when not turning if you have a diode that is bad or going bad. But your drain seems kinda small for that. But I am no expert. Try diconnecting your alternator and doing the test again.

BTW. I had a pita drain in my car and found that my glove compartment light wasn't going out when the door was closed. The bright side is that it was easy to fix.

Alan

Good suggestions in general (+under hood light on later models too) but the current is too low for any of these I think... lights are 5W or more so more like 400mA+...

This dropping to 20mA after battery disconnect seems to be the key clue (and rules out a bulb/alternator) - assuming that is repeatable.. What do you have to do to reinitiate the higher current...

Switch to accessory, Switch to Ingition - other....

If you do disconnect the alternator to test - maintain the onward connections (bolt them back together off the alternatoir) or you will have disconnected almost everything...

Alan

michaelathome

As to the clock and where it is getting it's power I am not sure of the fuse but I can tell you that it is also powering the gear select illum on my '88, I have the clock disco'd and the light for the shifter w/away as well but all the other lights in the dash seem to be working at this time.

Michael

Alan

Michael,
On an '88 its on the interior light fuse #24, your instruments should not be on this fuse - your gear select should not be on with the car off either - seems someone screwed with it....

Chalk another up to the PO's

Its the same on an '87.

Alan...

Flott Leben

Alan, you really are the expert on this! That is just the diagnostic test I was trying to come up with. The 85 to 20 mA is repeatable but what I was doing was starting the car up each time to restore the increase. I did not think to turn the ignition to the first position and check amperage, then turn to the second position and check amperage . . . I will try to get to those tests later in the week. (I don't know why my window on/off drain seems low - weird.)

Note: I do have seat warmers, the fastern seat belt "gong" never sounds but the light in the center console always stays on and the hood light never lights up. That brings up a good question - how do you activate the hood light anyway? Do the headlights need to be on?

Thanks all!

Bill Ball

Alan:

Yes, the window relay pulled 100 ma. I was just using that as an example of a relay that stuck on. He has another problem if the drain is there despite pulling all fuses, so I gave him what worked for Dave and I in dealing with a mysterious drain.

Flott:

Pulling the connectors on the bottom panel is not very time consuming. Pop off, look at meter, pop back on. 10 seconds each. Make up 10 short jumpers with male and female spade connectors once you find the connector with drain. If you are smart, you may not need that last step.

Flott Leben

Thanks, Bill. I didn't realize they just pop off. Is it pretty obvious how they come off by looking at them or is there a special trick to not breaking them?

Bill Ball

I think there is a sliding clip??? I dunno. Dave popped them off and on while I watched the meter at the rear of the car.

Alan

Pull the big red tab towards you - about 3/8 inch - it unlocks the plugs. lever the plugs out starting at the top - there is a very brittle locking tab at the top - move it only enough to clear... then bottom/top/bottom/top alternating. There are 2 little tabs with holes on eavch plug - if you have a hooked puller tool - pull on those - if not bend a larger paperclip and put a tight hook on each end. I recommend not pulling directly on the wires...

If you do break some top tabs.. not a really big deal - they are just insurance - mainly they tell you that you are all the way seated - the plugs are not going to come free - the lock at the bottom will see to that. I have one or two that died...

On the 91+ the underhood light always comes on with the hood open - on earlier cars incl. yours it only comes on with the marker lights on and with hood open (via a mercury tilt switch).

Alan

SharkSkin

Alan, those tiny pull tabs can break off pretty easily. Fortunately they are non-critical, but I think that on any panel that's less than pristine the extra effort required to pull the connectors is just too much for those tabs. At least I've found that to be true on the couple of later cars I've been that deep into.

As Alan and Bill have been saying, it's a process of elimination. This latching drain that you say goes away when you disconnect & reconnect the battery -- Some other ways to help narrow it down, since you've already pulled the fuses to no avail:

-Pull the connector off the fan controller, under cover between the passenger door and the passenger seat. Bill & I found a significant drain, ~100mA IIRC, on one car. Also try the one under the hood, to the left of the latch as you face the car.

-Pull the B+ feed wires off the top of the CE panel -- this will help eliminate anything in the panel.

-Separate the wires at the jump post.

-Remove the smaller + wires from the battery one at a time.

That first item is easy to get to, and likely to get rained/spilled on over the life of the car. The others may help you narrow the problem to a specific area.