Turn signal problem

[John4759]

Hi I have 2001 C3500. I am having a problem with the turn Signals, they will not work unless the brake pedal is depressed. Does not make any difference if the ignition is on or off. I replaced the brake switch, but no luck. I just bought the truck but the last owner said it didn’t do it before. Any help would be be appreciated.
John

 

[Will L.]

First check the correct bulbs are in there. I’ve seen single filiment lamps where it should be dual cause this. Could happen the other way around also.
Check the grounds for those lights, could be they are only working through them.

Be leary of aftermarket LED.

 

[John4759]

First check the correct bulbs are in there. I’ve seen single filiment lamps where it should be dual cause this. Could happen the other way around also.
Check the grounds for those lights, could be they are only working through them.

Be leary of aftermarket LED.

Thanks for the help. This truck has an aftermarket utility body the lights are LEDs. I had to rewire a few because the plug ins were corroded. Everything works except The turn signals need the brake being applied.

 

[Will L.]

I suggest using a simple testlight with the LEDs removed. Get the power to eork on just the wires like it should before adding the mess of LEDs. I have seen SO MANY issues from LED that gets complicated quickly.