Front Flashers/hazards work while rear do not
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Front Flashers/hazards work while rear do not
Hi all, I've had a little issue I've been working on for a while on my 1982 F100.
My front turn signal, hazards work. The rear brakes and running lights work, while the rear does not flash for the turn signals or hazards.
I have replaced the turn signal switch in steering column (turn signals didn't work at all till I did this nor the horn), the relays on the front and back of the fuse block, and the bulbs on the rear lights.
Is there something I'm missing, that controls the rear flashers? The rear lights are aftermarket and all the wiring appears to be run properly. There indicates ont he fuse block that at one point the #4 fuse blew in it's socket, however I reqired that to bypass the block temporarly so I don't think this is the issue (my book says fuse 4 is "Exterior Lights and Instrument Illumination"
Thanks!
My front turn signal, hazards work. The rear brakes and running lights work, while the rear does not flash for the turn signals or hazards.
I have replaced the turn signal switch in steering column (turn signals didn't work at all till I did this nor the horn), the relays on the front and back of the fuse block, and the bulbs on the rear lights.
Is there something I'm missing, that controls the rear flashers? The rear lights are aftermarket and all the wiring appears to be run properly. There indicates ont he fuse block that at one point the #4 fuse blew in it's socket, however I reqired that to bypass the block temporarly so I don't think this is the issue (my book says fuse 4 is "Exterior Lights and Instrument Illumination"
Thanks!
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From: Northeast, OK
My guess is that there's a ground problem at the rear. The other lights can sometimes work by using the other bulbs as ground, but things will work oddly. Anyway, check the ground wires to the bed on each side.
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One question, coming off the back I found a brown wire, along with the brake and turn signals - I can't find a brown wire on my diagram I have. any idea what it's for?
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I think I've still got an issue.
PO has a wire running off of the relay at the brake to the back lights (green wire coming off 'relay' or whatever this is). So I wired that along with brown to aftermarket taillights brown wire. turn signals appropriate to each light. Works all the time when truck is at rest, then if I take it and drive for a couple minutes, they all stop working in the back, while fronts still work. then later after truck has been sitting, they work again.
These are LED aftermarket lights, not bulbs, if that makes a difference - I just imagine that something isn't grounded right but the wires are grounded right to the mounting bolt and metal mounting braket and I sanded lightly all connectors to make sure there wasn't any contact issues.
I guess I figure this green wire is supposed to not be in the mix at the back? Supposed to run somewhere else?
any advice would be appreciated, thanks.
PO has a wire running off of the relay at the brake to the back lights (green wire coming off 'relay' or whatever this is). So I wired that along with brown to aftermarket taillights brown wire. turn signals appropriate to each light. Works all the time when truck is at rest, then if I take it and drive for a couple minutes, they all stop working in the back, while fronts still work. then later after truck has been sitting, they work again.
These are LED aftermarket lights, not bulbs, if that makes a difference - I just imagine that something isn't grounded right but the wires are grounded right to the mounting bolt and metal mounting braket and I sanded lightly all connectors to make sure there wasn't any contact issues.
I guess I figure this green wire is supposed to not be in the mix at the back? Supposed to run somewhere else?
any advice would be appreciated, thanks.
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From: Northeast, OK
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yes I have that diagram but just above the brake there is what looks like a relay with two green wires coming off of it, that the PO ran a wire from one of these green to the back that seems to power the lights as a 'brake light' but as the diagram goes I don't see that there should be a green wire terminating back there. Note that I put 'relay' In quotes because I am unsure what it is, I didn't find it in the diagrams.
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The brake switch has two light green wires - one with a red hash that would be hard to see and the other just plain. Might that be it?
And, he may have tapped in there because of a problem with the turn signal switch. As you can see in the diagram, there's a lot going on in that switch and it doesn't take much to cause problems. So, he may have bypassed it.
And, he may have tapped in there because of a problem with the turn signal switch. As you can see in the diagram, there's a lot going on in that switch and it doesn't take much to cause problems. So, he may have bypassed it.
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The brake switch has two light green wires - one with a red hash that would be hard to see and the other just plain. Might that be it?
And, he may have tapped in there because of a problem with the turn signal switch. As you can see in the diagram, there's a lot going on in that switch and it doesn't take much to cause problems. So, he may have bypassed it.
And, he may have tapped in there because of a problem with the turn signal switch. As you can see in the diagram, there's a lot going on in that switch and it doesn't take much to cause problems. So, he may have bypassed it.
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If he spliced in and didn't eliminate the run to the turn signal switch then the switch should still be getting its feed. I'd use a volt meter to check between the wire and ground when you push on the brake. Use a needle or pin to penetrate the insulation - but don't stab yourself. Trace the signal into and then out of the switch and see where it goes away.
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If he spliced in and didn't eliminate the run to the turn signal switch then the switch should still be getting its feed. I'd use a volt meter to check between the wire and ground when you push on the brake. Use a needle or pin to penetrate the insulation - but don't stab yourself. Trace the signal into and then out of the switch and see where it goes away.
No he cut the wire that's why I can't tell where it should have gone. The switch is still sending the volts, it's what I'm using right now to just power the brake lights and disconnected the running lights for now. Do you have any idea what pin it would have been on the harness? I think he yanked the whole wire out of the harness because I don't see any cut wires on that harness. This would be why I haven't been able to figure this out!! Thank you
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What I was saying was he ripped it out of the harness, so I don't know what pin out it would be and I don't see a diagram for that harness anywhere. Never mind I'll try to figure it out by going to a junkyard. Thanks for your help.
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From: Highlands Ranch, Co
That has been my best solution of late. Previous butchers AKA Owners of these old truck are notorious for "temporary fixes. "
I got a 67 that has been on my dads (RIP) farm its whole life and I get more information from just looking at what stock looks like.