Problem with directionals in a l989 gmc sierra p/u

chevrolet
1500

#1

hi am having a problem with my truck - my directional don’t work - well they work when the lights assembly is not screwed into the body of the truck - changed all of the bulbs, new circuit boards and checked all the fuses (even brake fuse) - when the tail lights are put back together they don’t work - the running lights & break lights work ok but no the directional - what is the cause - is it a multidirectional switch or is it a bad wire - it has been in the shop 4 times for the same thing - am at the end of my wire with this one? Truck has no body rot on it and runs like a top - it has a 350 chev 5.7 in it that came out of a suburban - use it for farm work, dump runs and hauling hay - so what is up with the directional - also want to know how much it should cost to repair a intake manifold leak? - again thanks for any help - it is a K series for what it worth


#2

If they work outside of the body cavity and the circuit boards have been changed, it leaves really only one possibility- the wire for the directional lamp is failing in the harness connector that plugs onto the lamp assembly. While it is out of the body cavity, wiggle the harness wire for the directional lamp where it enters the connector. I’m betting it will become intermittent then.

Make sure the terminal is fully seated in the connector, the mating end is not buggered up and that the crimp end is solid both mechanically and electrically. Sometimes, if they are close to failing completely, if you tug on the wire end, it separates at the break or at least the insulation stretches easily, compared to the other wires which will feel solid…


#3

My thought is there is a positive to ground short. Pos juice is shorting to the assembly, it works when disconnected, but goes directly to ground bypassing go when assembled. My take you have a short somewhere. An ohm meter can verify.


#4

@minismom

I just looked up, and Chilton says 4 hours labor to reseal intake manifold

That is just a guideline, so a shop may charge more or less labor

And not all shops will have the same labor rate

:smiley:


#5

I think you have a half broken wire in your assembly tail lights .