Interesting light issue

[scoutdoors1000]

I have searched the forums and tired many things for similar issues but just today ran into something quite interesting with regards to my lights.

Prior to today:
My passenger blinker was a slow blink (original blinker switch went bad and replaced with what is comprable to flasher switch). Driver side front would stay solid with nothing in the rear. Drivers marker/blinker would be solid.
Both sides had no running lights in the rear. Both head lights worked.
(Summary no rear running lights, no rear driver blinker, slow passenger blinker front and rear, Good rear passenger brake light, no driver brake light)

Attempted fix. Checked bulbs. Checked wires where rubber boot plugs into tail lights. Got the same above results. Checked fuses, all good but some old. Pulled fuses and sprayed all with electrical contact cleaner.

Today (After electrical contact cleaner)
No driver blinker (not even solid), Slow passenger blinker. Good passenger brake light, No driver brake light. No rear running lights.
Now the interesting part....ALL this can happen with the ignition off and no key present, just as long as the switch is set for the lights to be on. All I did in addition was to literally push on some wires in the harness, find a strange wire with a bulb burned out that is grounded to the ground just above the Parking brake, and use the electrical contact cleaner.

Please help......

 

[Warthog]

Check the two ground wires that are on the radiator support above the headlights. Those two wire cause some stange problems.

 

[scoutdoors1000]

checked. Tight. Driver side with exposed wire but appears to be intact otherwise.

 

[ChiefMinion]

You aren't going to want to hear this as it can be tedious. I had some similar trouble, though not as complex as yours.

What I ended up doing was pulling each bulb. (You said you already checked them so that's out of the way.) Make sure the contacts in each socket are clean. Make sure there is current to the bulb by checking the voltage to the frame. Then identify the ground tab in each socket. With the lights off, check the resistance from the ground tab in the bulb socket to the frame. As previously posted, the grounds on the frame could be the problem. It could also be a problem anywhere along the ground circuit. If you don't have zero, or nearly so, resistance from the ground tab in the socket to the frame, then you have to trace from the ground in the socket to the frame and find the problem. I had one where the ground wire wasn't pressed firmly into the socket.

I'm sure there are other possible explanations, but this is where I would start.

 

[scoutdoors1000]

Tedious but genius. So the question is....I used a simple bulb wire combo to test the sockets in the back. I actually tested at the rubber boot where the tail light harness plugs into a vehicle side harness. At that point, with my little bulb I could not get anything to light up buth using the frame ground and the wire ground. IS this sufficient for the above mentioned test or not?

 

[ChiefMinion]

Well, I use a cheap multi-meter. But the bulb should be able to tell you if there is power to the socket. If you can't make the bulb light up even grounding to the frame, it sounds like like the problem is with power to the socket, not the ground.

The wiring diagrams in the TMs give you wire colors for each circuit and will be a great help in tracing things back to the source.

Couple other things I've noticed with older vehicles may help. A slow blinker often means one of the lights on that side is burned out (bad ground, etc) or one of the bulbs is not the specified type. Also, the problem can often lie some distance from the symptoms. For example, a bad ground on a turn signal can make the turn signal indicator light in the dash light up when you turn the lights on.

Be methodical and stick with it.

 

[Oldsouthernboy]

under the tail light on both sides, that is under the tail light base is a ground, pull it the light out, clean the ground, scrap clean, grease, reassemble the light assembly, repeat to the other side, then do both front engine grounds, clean grease, I believe you have all ready done that, but recheck, unhook the batteries, clean the terminal strips. Check the black out grounds in the rear to. and replace your flasher module if when the turn signal is to be working and it not clicking, use a heavy duty replacement.

 

[scoutdoors1000]

Thanks everyone for the input. Walked through things from the back forward once again thanks to y'alls suggestions. S Starting with the bulbs forward....after checking heat at the fuse block of course. This time though, to make it easier I got a true light tester and started poking holes in wires. I did have a loose ground at the driver side rear light which I am nut sure if this contributed. What I did find however was a bunch of chewed up wires. Never again will I trust a few monkeys to put on a trailer hitch. They chewed up my wires right where the bolt went through. The reason for the strange symptoms...Intermittant shorts and intermittant completion of circuits. Cut out the bad section and replaced....now working like a charm. (the wire was cut in a spot that I could not see. Had to literally stick a bunch of holes then narrow it down and felt with my hands. Then pulled off the bolts in the rear and pulled the whole rear light wire harness to past the gas tank.

Old southern...thanks for the rear ground suggestion


Chief thanks for the slow blink suggestion.

Warthog thanks for getting me started in the right direction.