Troubleshooting Wrong Bulb Filament Lighting Up with Running Lights

Question:

Hi When i use on my left turn signal the turn signal filament does not blink but the running light blink what can be the problem Thanks

asked by: Hamid F

Expert Reply:

It could be that there is either a mis-wired trailer connector, a mis-wired light or that the presence of corrosion in a connector has the running light circuit linked to the turn signal circuit. You could also have a bad bulb with a damaged filament.

You can try a new bulb to rule that out as a cause. Check all your wiring connectors for any signs of trapped dirt, moisture, corrosion or discoloration and clean or replace as needed. You can also check that your stop/turn/tail light, such as Optronics # ST70RB, is properly wired so that the combined stop/turn signals are going to the correct terminal.

On 3-wire pigtail # A45PB the white wire is ground, the black wire is for tail (running) lights and the red wire is for stop/turn signals.

expert reply by: Adam R