'85 electrical issues
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'85 electrical issues
I'm still having electrical problems with my '85. I tested for voltage on the positive battery cable at the starter and only got 3 volts... the same amount i've been finding everywhere else on the car. At the other end of the cable I have 12.5 volts. Does this mean there's something wrong with the cable, the battery, or am I completely off?
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im no electrican, but sounds like pos. batt. cable. Ohm test it?
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Le Mans Master
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From: Tampa Florida
You'll want to unhook the battery before you do this test.
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I'm an idiot when it comes to electric stuff, the battery was never connected so of course there would be no voltage at the starter 
However, turns out when I fixed the fusible link last year I didnt solder one end good enough and it broke loose. I fixed it and now I have full power to everything, it even cranks over... but the fuel pump wont kick on! So now I need to look that up.
However, turns out when I fixed the fusible link last year I didnt solder one end good enough and it broke loose. I fixed it and now I have full power to everything, it even cranks over... but the fuel pump wont kick on! So now I need to look that up.
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Thread Starter
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From: sw Ohio
I checked the FP fuse and it was good, even threw in a new one just to be sure and no change. Theres no voltage at the fuse block for the FP fuse either. I checked for voltage at the FP relay and theres nothing going in or out. The book says to apply 12 volts to terminal G on the ALDL, is there another terminal that has 12 volts I can to G?
Last edited by Demonic85; Feb 11, 2009 at 06:05 PM.
Le Mans Master
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I checked the FP fuse and it was good, even threw in a new one just to be sure and no change. Theres no voltage at the fuse block for the FP fuse either. I checked for voltage at the FP relay and theres nothing going in or out. The book says to apply 12 volts to terminal G on the ALDL, is there another terminal that has 12 volts I can to G?
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BTW the pump is a brand new AC Delco unit I got about a year ago along with injectors, filter, pump sock, and regulator. Assuming the pump does indeed run when I jump the terminal, what path is the most likely culprit?
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The fuel pump has a fuel relay on the firewall by the brake booster. You may want to replace the relay if you feel your's is at fault. Take a look at the wires that go to the relay to ensure they are not damaged or melted (several CF members have had this problem). If the cluster fuel gage shows "any amount" at all....the ground for the fuel pump is OK.. you just need the +12 to the pump.
Le Mans Master
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Yes I have already checked the grounds already, theres just no 12v like you said. The wires on the relay dont look so hot but theres no voltage on ANY of them even before the relay which makes me think the problem is elsewhere. The fuel gauge is working, got like 1/2 tank
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Yes I have already checked the grounds already, theres just no 12v like you said. The wires on the relay dont look so hot but theres no voltage on ANY of them even before the relay which makes me think the problem is elsewhere. The fuel gauge is working, got like 1/2 tank
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I jumped terminal G and the pump does indeed work. So now I agree with you guys that its most likely a bad fusible link but the wiring diagram posted before doesnt show me which one leads to the fuel pump circuit. Can anyone look in the '85 FSM and tell me where to find it?
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I got it up and running today, I just started testing every single fusible link I could find and turned out to be one near the battery that was bad. It runs just fine but throwing a code 54 now. Thanks for the help 
