Hi Everyone...

I have a 2006 F250 Superduty 4x4 that the brake lights hazards and turn signals have stopped working in the rear.. The middle cab brake light does not work either.. The running lights do work as well as the turn signal and all lights in the front.. I also checked the trailer plugs and both work for running brake and signal lights.. I have checked all fuses under the hood as well under the dash with a test light and i have nothing blown.. I have replaced the Brake switch as well as the flasher module under the dash and picked up a new multifunction switch (Turn signal/hazard) and that didn't help either.. I'm stumped at this point.. I have not checked the bulbs yet but wouldn't think they would all blow at the same time.. (will do this next).. Does anyone have any other ideas I could check.. Thank you..

 

I have the electrical diagrams for a 2009, but not a 2006. So it's possible they are different.

The 2009 shows the cab brake light works off the same circuit as the trailer brakes, so if trailer is working maybe the cab brake light is just burned out.

The rear turn/stop/hazard lights come off a different fuse in the Smart Junction Box than the front ones do, so that fuse could be at fault.

Tom

 

The 09 drawings aren't of any use for an 06 Super Duty. The electrical systems were changed dramatically between two model years somewhere between there.


There is no single point of failure that can take out both the high-mount brake light and the rear stop/turn signals while leaving the front turn signals and the trailer stop/turn signals operational.

Therefore, you have to have two faults that will need to be diagnosed separately.

If the trailer stop and turn signals work properly, that clears the flasher unit, brake switch, and multi-function switch.

Having blown all three bulbs is looking plausible... Pull them out and use your test light t0 see if anything is getting to them.

 

Thank you for the quick replies.. All 3 bulbs were blown... Wild I know I have never seen that before.. 1 was completely fried and had burn marks.. Replaced them all and now back up and operational.. Thank you again..