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Need electrical Jedi Masters help....

  • Thread starter Thread starter Mike86Stang
  • Start date Start date Aug 29, 2006

Mike86Stang

Advanced Member
Apr 11, 2000
10,296
0
77
Red Lion, PA
Aug 29, 2006
#1
  • Aug 29, 2006
  • #1
I have a odd issue that I've been fighting for months & I can't figure it out.

My dash lights won't work, & when I turn on the headlamp switch the fuel pump comes on with no key in the car. From what I can tell when things are going goofy (problem comes & goes) the fuel pump is picking up power from the EEC power relay. When I turn on the headlights I can hear/feel it click when it comes on.

When it's acting normal & I hit the lights the EEC power relay desn't engage & my dash lights work fine & the fuel pump stay off.

Another side note is that when I have the H/L switch in the parking lights only position the High Beam Indicator comes on the dash even though the headlights aren't even on.

Please HELP!
Thanks
Mike
 

Fett

New Member
Nov 2, 2004
766
6
0
Aug 29, 2006
#2
  • Aug 29, 2006
  • #2
First things first, have you owned this car for a long time? I ask because it could be a killswitch that was wired in wrong. I know a lot of people who use stock buttons as kill switches...sometimes for the ignition, sometimes for the fuel pump. Just a thought.

Secondly, have you pulled your switches to see if all the wires are connected properly? You might want to pull the headlight switch, hazzard switch, and multifunction switch and make sure all the wires are snug in the hardshell connectors. The pins that hold the wires into the hardshell connectors become brittle and break, allowing wires to slip out of the connector and thus not make contact with the switch it is connected to. Very common problem, and can have odd results.

Also test out your fuel pump relay, make sure it isn't stuck in a closed position. Actually check all your relays in this reguard, such as EEC relay.

Not sure if I am being helpful or not, I am just throwing ideas out there that I have run into which caused a bunch of odd issues.
 

Mike86Stang

Advanced Member
Apr 11, 2000
10,296
0
77
Red Lion, PA
Aug 29, 2006
#3
  • Aug 29, 2006
  • #3
Thanks for the reply...

So far I've replaced the combination switch / headlight switch / fuel pump relay so all are in good condition. I have not replaced the EEC relay, but it switches on & off I can feel it so I think it's ok.

Someone told me a circut was back feeding through another circut... I don't know how that works or what it means. I was told to look for a bad ground, but I haven't found any. Thanks again

MIke
 
S

stang2004

Founding Member
Sep 23, 2001
177
0
0
Northern Jersey
Aug 29, 2006
#4
  • Aug 29, 2006
  • #4
sounds like a wire is crossed or your having something jump a circuit. Electrical problems are the worst to try and troubleshoot. Good luck with it
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Aug 29, 2006
#5
  • Aug 29, 2006
  • #5
Mike, a latching EEC relay has been known to keep a FP working with the key off. Normally however, the relay latches with the key off (walkin away from your car and year hear the pump bangin away).

Though not a fix, you might end up installing a blocking diode to prevent the backfeeding.

I just don't know how the four eyed cars are wired up, so that's the best I got. I'm sure the whizzes in here can get your running straight in no time.

Good luck Mike.
 
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