Troubleshooting Trailer Connection and Instrument Panel Lights on 2007 Toyota Tundra

Question:

Noticed today after towing my horse trailer 7 pin my instrument panel in 07 tundra lights started flashing but when I hit my brakes the right turn signal turns on solid light and the r for reverse comes on even when vehicle is moving. If u hit manual level it will come on too it also turns on my back up camera monitor. This happens even if trailer isnt connected and n c shows on controller. Can the connectors corrosion possibly cause malfunction like this maybe replacing best truck plug ? Or is my trailer the culprit. Its only year old 2013 prodigy p2 installed from U-Haul

asked by: Krista M

Expert Reply:

It can be a bad ground. I recommend that you check the trailer connector for corrosion as you mentioned, but also check the ground on that 7-way connector. It should be metal on metal and free of corrosion and debris. Clean up your 7-way terminals with a small brush and see if the issue is resolved. It sounds like you have the issue even then the trailer isn't connected, but if it only happens when the trailer is connected, then check the main ground on your trailer in the same way.

Let me know if this doesn't solve the issue and we can continue to troubleshoot. It is safe to say that it is not your brake controller, but there is a short circuit issue in the system.

If you determine that you need to replace your 7-way, then I recommend the Hopkins Endurance Multi-Tow 7-, 5- and 4-Way Flat Trailer Connector # HM48470 for a universal fit or the # HM11143395 which is a factory 7-way replacement.

expert reply by: Jason S