Electrical Gremlin

Spievy · 08-31-2008, 05:07 AM

I have searched the forum but nothing seems to apply, so here is the deal. I have had this problem for a while.

If I don't drive my '86 944 for 5 to 7 days, my battery is dead. Battery is a few months old. Alternator is about 2 years old. And have checked/cleaned the ground points. Also just recently I did an amp test with the car off. I was pulling 3 Amps and climbed to 4 by the time I disconnected my multimeter. While I was checking the current draw. I pulled every fuse in the fuse panel to see if the draw would stop, it didn't. So I figured I would check the relays, same result. Lastly I CAREFULLY disconnected the Alternator wires and it Still was drawing.

I do believe the alternator is charging good, my voltmeter on the dash never drops below 13v even with full running draw. What should I check next?

ballysdad · 08-31-2008, 06:58 AM

The relays you pulled were in the fuse boxes I assume? Check to see if there are any relays under the dash that may be hidden. 3 or 4 amp draw is alot even for wire degradation. I am surprised that it didn't drop during the fuse pulling party. If the wiring is the culprit you can put a battery maintainer in if you cant find the draw.. I know what your going through had the same problem with my 84' na.

drew1 · 08-31-2008, 07:44 AM

Did you check the amps from the ground battery post to the unhooked ground battery cable?

If not try this & one by one unhook the extra wires off the positive terminal to see if you get a change.

Spievy · 08-31-2008, 09:59 AM

Ballysdad: I only pulled the relays & fuses in the fuse box located in the engine compartment (driver side). I didn't know there are relays in the cabin, I will check those.

Drew1: I did check the amp draw on both the negative & positive terminals. Also to rule out the alt ground. I did a Ohm test from the alt case to the unhooked negative battery terminal... 0.1 Ohms

Could it be the Alarm system, I don't have a key for mine but I would think that would have a direct connect to the battery?

hpservertech · 08-31-2008, 10:30 AM

The alarm does have a direct connection to the battery.

Spievy · 09-02-2008, 11:45 AM

Well, it is not the alarm (I tested it yesterday) and I can't seem to find any relays in the cabin.

hpservertech · 09-02-2008, 12:12 PM

If you pulled every single relay and fuse and are still seeing a 3amp/4amp draw then someone has hooked up something directly the the battery. The factory alarm is the only other thing that is wired to the battery.

From the battery there is the main + cable that goes to the starter. There is also a wire that goes to the alternator and another that goes to the alarm.

bland vanilla · 09-02-2008, 03:35 PM

Agreed on the source of the current draw. You got any aftermarket audio gear in there?

Steve

Spievy · 09-03-2008, 11:11 AM

I know it isn't the alarm, I disconnected it to test current draw. Also I had already disconnected the radio, to test current draw. Even with both of these disconnected 3 amps.

hpservertech · 09-03-2008, 11:26 AM

You obviously have something pulling power if all the fuses and relays are removed and you still have a 4 amp draw.

Can you show us any pictures of the battery terminals/cables?

Slam · 09-04-2008, 11:48 AM

Just a shot in the dark, but how about pulling each connector on the fuse block and testing again?

SolReaver · 09-04-2008, 10:08 PM

OK, just a bad idea. Disconnect the headlight motor. My electrical system is toast and the battery gets drained whenever I leave the motor attached. FYI it is all due to a PO who "hot wired" his headlights. It'll only take a sec to check and someone may have set perm hot to the relay in order to fix a prob in the past.

Spievy · 09-05-2008, 10:35 AM

I know the battery cables are good. I replaced them thinking that could be the problem, also zero corrosion on the battery terminals.

I will check the relay fuses again. Last time I pulled them individually and replaced if not change in amps. This time I pull absolutely everything at once (marking the relays do no confusion)

I will check the headlight motor, but I think that circuit is fused.

I will keep you posted, thanks for the advise

hpservertech · 09-05-2008, 11:40 AM

best thing I would say is take all the fuses out, then the relayx and then start taking the fuse panel off layer by layer. It's not all that difficult, just takes time.

Look up under the fuse panel also. Do you see any butt connectors or taps or splices? What about around where the DME is?

Lapponia · 09-06-2008, 05:23 AM

I second to that of removing fuses, relays and alarm unit. BUT do try to remove wire connection from battery to alternator. Could be a short in alternator or in its voltage regulator. My 2 cent. Good luck.

______________________________________
Lapponia 1944 na 1984

Spievy · 09-14-2008, 02:48 PM

Quote:

Originally Posted by hpservertech

best thing I would say is take all the fuses out, then the relayx and then start taking the fuse panel off layer by layer. It's not all that difficult, just takes time.

Look up under the fuse panel also. Do you see any butt connectors or taps or splices? What about around where the DME is?

Okay I got a chance to do this over the weekend. First I connected my multimeter, 3.19 amps (steady). I disconnected the starter wires and alternator, still 3.19 amps (so I ruled out the the starter and alt).

Next I pulled all of the relays at once, still 3.19 amps. Next comes all of the fuses, 3.19 amps. So now I have a completely empty fuse relay panel. I removed the panel and inspected all 100 or so wires, no nics or splices. Then I disconnected the 2 main power wires at the front and the reading dropped to 0.56 amps. So happily it looks like I am getting some where.

So now I reconnected the 2 power wires and it jumped to 3.19 amps. I carfully pulled all of the main wire connectors (they are color coded and have a Letter next to them). I finally got to the "F" brown connector and it dropped to 0.56 amps. So it seems to be in wire block "F".

Now I figured I would reconnect the relays and fuses ( with F disconnected). Connected all of the relays, 0.56 amps good. Now the fuses are a diffrent story.

With wire block F disconnected the following fuses when connected would bring the amps back to 3.19 amps

Fuse # 11 - Int. light, clock, cig lighter, tailgate
Fuse # 14 - Fresh Air Blower
Fuse # 39 - Radio (As for the radio my first testa couple weeks ago I pulled the radio out of the car.)

So now what?!?!?!?

hpservertech · 09-14-2008, 03:26 PM

Factory or aftermarket radio?

Take the trim off for the dash where the clock/cig lighter is. Once you do that inspect the wires for the cig. lighter.

hpservertech · 09-14-2008, 03:32 PM

If it's aftermarket, how did you remove the radio? Did you just disconnect the harness from the head unit?

Like I said before, I bet it's the radio that's causing the draw. If it's aftermarket then do yourself a favor and cut the wiring harness out, or at least cut the ground wire (usually black).

If you dont know the wiring and it is after market let me know and I can help you with that part.

Spievy · 09-14-2008, 04:08 PM

It is a blaupunkt aftermarket. And yes I disconnected the radio from the wiring harness in the dash. However I am sure the ground for the radio is at the stock position. I will pull the connectors off the cig/lighter, I have in the past seen the wires and nothing has been spliced there.

Do you know what the connection block "F" feeds?

hpservertech · 09-14-2008, 04:30 PM

Not positive. But you already isolated it to a very large degree.

With that big of a draw I would still cut the wiring harness. if you do it right you can still splice into it. It's just sounding like the harness is your cause.

While the harness is still in though, pull the fuses on it. There should be at least a 10amp fuse on the harness.