How to fix a Turn Signal Relay in a Chevy Silveradoby Contributor
Replacing the turn signal relay or flasher is a relatively quick fix when you have problems with your turn signals. It may not require you to replace the flasher relay however and may only be a bad bulb in one side or the other. Follow a quick checklist to fix the problem and have your truck running again.
Start the car so that when testing the lights you won't run down your battery. Have a friend help you check the lights. You sit in the car and operate the lights having them tell you which lights turn on and which turn off. Check the turn signals one at a time and then test the hazard lights. Be sure that your friend looks for the lights when you can hear the lights operating at a slower or faster speed.
Check each of the turn signal light bulbs, especially the bulbs that you found not working. Most often, a bulb that burns out triggers a problem with the turn signal relay.
Replace any burned out bulbs and retest the lights. In the best situation, this will fix your problem with the turn signals. If not, move on to checking the fuses for the turn signals and hazard lights. The fuses for these are located on the driver's side of the cab on the left side of the steering wheel. They should be in a fuse box mounted to the outside wall of the cab.
Open the fuse box and using the diagram on the underside of the lid, check the fuses that have anything to do with turn signal lights or hazard lights. If all these fuses check out, then the problem is most likely the flasher unit or the multi-switch on the steering column.
Look above the fuse box under the left side of the dash to locate the flasher unit. The flasher is a square unit that looks like a relay. It will have its own receptacle mounted separately from the fuse box. Remove the flasher and test its operation. You may have to take this to the auto parts store to test. If it is bad, replace the flasher. Re-check the operation of your turn signals. If this doesn't fix the problem, then you will need to replace the multi-switch, or turn signal switch, on the steering column.
Remove the steering wheel with a steering wheel removal tool and then remove the plastic covering that houses the switch. Carefully remove the switch and replace with a new one. Be careful to reconnect all the wires to the same positions on the new switch. Reassemble the coverings and remount the steering wheel. Retest your turn signal lights.