Electrical issues - searching for any 944 gurus...

Posted this in other places.. but I'm desperate.. It's going to take someone who's either been there.. or knows a lot to figure this one I think. I might be on my own....

OK. I found I do have a bad alternator, so I am buying a new one but even with the alternator not connected I am still having issues. If it is somehow that the alternator needs to be hooked up , let me know, but I don't see any reason. It was doing this even with the bad alternator. alarm box is removes and jumpered the way described at clarks garage.

I just got done a rebuild (engine out) and I installed iceshark battery cables, and removed the stock alarm.. Really crazy things are going on.

If I hook up teh battery cables to the battery everything is fine. 12 volts constant to pin 86 on the DME and ignition relays. 0 volts to pin

85, i believe it was.

Pin 85 should get 12 volts when the key is turned to the on position, energizing relays and whatnot. Key on - 12 volts comes to pin 85 as expected, fuel pump turns on.

Turn key off - RELAYS STAY ENERGIZED - fuel pump continues to run - ! light is on on the dash, even with key out.. 4 volts at pin 85 (this is where the problem is, I think?). The 4 volts is just enough to keep the relays energized, and from tripping off. a VERY LIGHT flick of any relay trips it off, ! light goes off, and everything appears normal. Not sure if 4 volts is still coming from the ignition switch or to the power of teh alarm relay area, I'll have to check that again.

It is clearly the 4 volts holding the relays open because it is very easy to flick a relay and get it to trip off - 4 volts is barely holding them energized.

Even more whacked....

Passenger headlight only works on normal beam. Brights shut the passenger headlight off. Headlight pins voltage. - Ground is good ground, upper pin (yellow wire) gets 12 volts on brights (maybe vice versa but regardless). last pin (white wire) - 12 volts on normal lights on.

I believe it is the yellow wire, where you see the 12 volts with teh brights on (or normal lights on if i have it backwards).

I've pulled each relay one by one, and it acts the same. So it's nto a relay I don't think. I've tried 2 DME relays, 2 headlight relays, etc.

If the battery is low (from the fuel pump running) turning the key on and off will shut it off. (probably because only 2 or 3 volts is holding the relays.. just a guess).

STRANGEST THING - BOTH HEADLIGHT PLUGS TEST THE SAME VOLTAGE.. yet the passenger headlight doesn't work on high beam. I've tried multiple bulbs, including teh one from the driver side that works right.. they all don't work. IF i pull the headlight plug off just enough to test, there is no voltage where it should be.. most likely meaning somethings shorting when there is a load.

for the past two days I've checked around for voltages with a multimeter.. spent 5 hours yesterday studying circuit diagrams with my dad.. and no luck finding anything.

I've disconnected the supplemental positive from iceshark battery cables and it makes no difference so it's not that.

oh , i like i said, i have the alarm plug jumpered 1-4 and 7-8 like clarks says. I don't have the alarm parts anymore.. so that isn't an option but I have a feeling it is bigger than this...

My only possible idea I can think of - Ignition switch. Is it possible the ignition switch is leaking voltage through, or would i be the first ever to have that happen? Doesnt make much sense for the headlight issue, since that is with the key on..

help!!!!! Car runs fine... I've driven it a few miles but i can't drive it with this wiring issue draining the battery and everything.. starting to have ideas of parting this thing out, after rebuilding it for a year and a half. This sucks.

Reply to
Yieldsign2
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Reply to
Regal53

Do you have a ground running from the engine to the frame?

Reply to
darthpup

You also need to place the multimeter in milliampere mode and in series with the battery to ground to see if you have a ground fault. With the key on and off of course. Battery voltage should be 13.8 when fully charged.

Reply to
darthpup

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