Tail light issue. 1988 1/2 ton.

I have a 1988 Silverado 2wd 1/2 ton. I have recently encountered an issue with the rear running lights. When I turn the running/headlights on I have no brakelights, rear signals or rear running lights. Also the dash lights dim when applying the brake or using signals while the headlights/running lights are off. I have tried Fuses and checking for power to rear tail lights with an ohm meter and they had power. I am at a loss thus far. If anyone has any suggestions on what it may be I would be more than thankful. Thanks.

I have a 1988 Silverado 2wd 1/2 ton. I have recently encountered an issue with the rear running lights. When I turn the running/headlights on I have no brakelights, rear signals or rear running lights. Also the dash lights dim when applying the brake or using signals while the headlights/running lights are off. I have tried Fuses and checking for power to rear tail lights with an ohm meter and they had power. I am at a loss thus far. If anyone has any suggestions on what it may be I would be more than thankful. Thanks.

Best I remember they have problems with the rear tail light unit.
If all else fai;ls replace it.
Check rear bulbs and sockets and the unit and also good voltage to them and good ground.
Also any trailer light wiring tied into rear lights.
Let us know how it goes.
Good Luck

I have a 1988 Silverado 2wd 1/2 ton. I have recently encountered an issue with the rear running lights. When I turn the running/headlights on I have no brakelights, rear signals or rear running lights. Also the dash lights dim when applying the brake or using signals while the headlights/running lights are off. I have tried Fuses and checking for power to rear tail lights with an ohm meter and they had power. I am at a loss thus far. If anyone has any suggestions on what it may be I would be more than thankful. Thanks.


with a voltmeter measure the voltage at the lamps that are dim. measure accross the lamp using the wires to the bulb..

then place the negative meter lead to the metal vehicle body . see if you now get the full 12 plus volts..

it this is the case you have a bad ground...remove and clean all grounds... if not this may be a fusible link or ????

with a volt meter trace from battery to fuse box for voltage drop..could be bad fuse sockets..this can take some time and patience..