Troubleshooting No Brake Lights When Towing with a 1999 Bounder

Question:

I have turn signals hazards and tail lights... But no brake lights. The tow plug is four prong...all works but brake lights...Ive checked all the fuses and breakers and change the brake pedal switches ???.. no results? There are two relay switches under the dashboard that might be the problem, but I havent figured out how to unplug and swap them or check them if I can get the little things out !??

asked by: Ric F

Expert Reply:

Since trailer brake and turn signals run on the same wires for a trailer with a 4-Way flat connector it makes me wonder if you have a converter like part # 118158 installed on your trailer.

Either way, what you need to do is start off by checking your vehicle and trailer connectors for any corrosion or debris. If those look good then move on to checking the connector on your tow vehicle with a circuit tester like part # PTW2992. Check your stop/turn pins to make sure that your vehicle is sending out the signals. Once you do this it will help you figure out if the tow vehicle or the trailer is the problem and you can move on to inspecting the wiring and the grounds for any damage or corrosion that may be causing issues - replace as necessary.

If you are still having problems after this your best bet is to take your towing setup to an experienced electrician to get some fresh eyes on the situation.

expert reply by: Jon G