Electrical craziness
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Electrical craziness
Hi All,
Trying to pin down the electrical issues on my 86 F250. First the starter would stay on and not disengage. It was nuts. Then the key stopped working...Had to turn ignition on and jump solenoid. Then the back up lights stopped working. Now the fuel pump stays running at all times. I have to disconnect the battery or it will kill my battery in a few hours. All these things are still current issues. I changed all the battery leads, new starter, new solenoid, and new reverse lights switch on the transmission.
Where would you start to chase down the faulty wire/wires? I don't know where to begin.
Thanks!
Trying to pin down the electrical issues on my 86 F250. First the starter would stay on and not disengage. It was nuts. Then the key stopped working...Had to turn ignition on and jump solenoid. Then the back up lights stopped working. Now the fuel pump stays running at all times. I have to disconnect the battery or it will kill my battery in a few hours. All these things are still current issues. I changed all the battery leads, new starter, new solenoid, and new reverse lights switch on the transmission.
Where would you start to chase down the faulty wire/wires? I don't know where to begin.
Thanks!
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Joined: Jan 2001
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From: Virginia
I bet the fuel pump is running all the time because you have the wires mixed up at the starter solenoid on the fender. There is a fuel pump priming wire over there that powers the fuel pumps when cranking only.
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Not sure how you adjust an ignition switch. I have replaced that as well. I should have mentioned.
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FTE Legend
Joined: Nov 2015
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From: Angier, NC
If it was the switch you replaced the screws holes had slots to move it.
IIRC you disconnect batt. first. there is a hole on the switch to install a pin to make sure the switch part is in the right position. Lookover your old switch.
Then I think it was key off put the rod into the switch and screw it into place, pull the pin, hook batt up and it show work if everything else is good.
If the switch is not set right it could be in between say start & run OR off & run.
I would need to check my book but I think that's how I did it months ago.
Dave ----
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I had a problem with my stock 460 fuel pump staying on and it was because of a bad starter solenoid.
The fuel pump gets power from the “I” terminal of the starter solenoid when the starter is engaged and my starter solenoid failed in such a way that the I terminal stayed hot all the time, leaving the fuel pump running all the time, until the battery drained. Also because a prior owner replaced the fusible link with a larger gauge this problem also resulted is melted, fused together wiring that cross fed other systems...
Disconnect the small wire from the I terminal of your starter relay and check to see if it has power with the battery connected and the key off. If the pump doesn’t run with the wire disconnected, and you have power at the I terminal with the key off, then your starter solenoid is bad.
The fuel pump gets power from the “I” terminal of the starter solenoid when the starter is engaged and my starter solenoid failed in such a way that the I terminal stayed hot all the time, leaving the fuel pump running all the time, until the battery drained. Also because a prior owner replaced the fusible link with a larger gauge this problem also resulted is melted, fused together wiring that cross fed other systems...
Disconnect the small wire from the I terminal of your starter relay and check to see if it has power with the battery connected and the key off. If the pump doesn’t run with the wire disconnected, and you have power at the I terminal with the key off, then your starter solenoid is bad.
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It is hot. I had already done this test yesterday but didn't have time to post. The whole thing is hot with the key off. It's a new solenoid but I guess I will put another one in and try that. The starter stud is also hot on the soleniod
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From: Virginia
I would pull all the wires off the small terminals on the solenoid. If the small studs are still hot on the solenoid, you do have a problem with the solenoid. If they are now not hot, and the power is coming from one of the smaller wires you just took off, it would not be a solenoid problem. Also when you pull the smaller wires off, does the fuel pump quit running all the time?
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