Turn Signal and brake light.

[350chevy719]

Passenger side both are out. Still have taillight. I've changed bulbs (numerous times), I've changed the board, and checked fuses. It flashes quick on gauge panel. And front passenger flashes quick but rear does nothing? Any ideas?

 

[Bob L]

Start with a test light at the plug and see if you have power there. If you have a fast blinking front and the other lights are working I suspect a poor connection between the tail light plug and the bulb holder board. The aftermarket replacement boards need to have the bulb wiggled around sometimes to get them to work.

 

[someotherguy]

Or the wiring is damaged or being interfered with by an added trailer harness. You can save yourself some headache by checking at the disconnect from the main harness at the end of the driver's side frame rail; there's a flat connector which ties the harness coming from the front of the truck to the rear lamp harness. Test on the truck side. If all is well there (and generally it will be) then you can continue down the path. Sometimes even the nice T-connector trailer harnesses where you don't have to tap anything in, can still cause problems.

Richard

 

[350chevy719]

Or the wiring is damaged or being interfered with by an added trailer harness. You can save yourself some headache by checking at the disconnect from the main harness at the end of the driver's side frame rail; there's a flat connector which ties the harness coming from the front of the truck to the rear lamp harness. Test on the truck side. If all is well there (and generally it will be) then you can continue down the path. Sometimes even the nice T-connector trailer harnesses where you don't have to tap anything in, can still cause problems.

Richard

There is a trailer system on it so maybe that could be the problem. Ive been wanting to remove it since I don't ever tow anything large enough to need the extra wiring and headache of it all. Thank you! I'll take a look here in a little bit