I RECENTLY ADDED SOME EXTRA BACK UP LIGHTS TO MY 2000 F250 7.3 POWERSTROKE. I DONE IT THE QUICK WAY BY TAPPING INTO THE BACK UP WIRING. IT WORKED O.K. BUT OCCASIONALLY WOULD BLOW THE 10 AMP FUSE UNDER THE DASH. SO LIKE ANY DAREDEVIL SHADETREE MECHANIC WOULD DO, I UPPED IT TO A 15 AMP FUSE, THEN JUST FORGOT ABOUT IT FOR A WHILE BECAUSE I WAS DOING DAYTIME DRIVING AT THE TIME. THEN ONE OF MY EXTRA LIGHTS GOT BUSTED UP REALLY BAD! HAVING SEEN THAT, I CHECKED TO SEE IF THE FACTORY LIGHTS WERE STILL WORKING AND THEY WERE NOT. NOW I HAVE A LITTLE EXTRA TIME ON MY HANDS SO I BOUGHT A RELAY, NEW SET OF LIGHTS, RAN A FUSED "HOT" DIRECT FROM THE BATTERY TO IT AND USED THE OLD "TAPPED IN" WIRE AS A TRIGGER.....HOOKED IT ALL UP, (PROFESSIONALLY THIS TIME), PUT HER IN REVERSE AND.....NOTHING !!!! I CHECKED THE UPPED 15 AMP FUSE FIRST, BUT IT WAS PERFECTLY FINE, CURRENT WAS GOOD. I USED A PROBE STYLE TEST LIGHT 5 OR 6 TIMES WHERE I HAD TAPPED IN TO THE FACTORY WIRE AND THERE IS NO CURRENT GOING TO THE BACK OF THE TRUCK AT ALL. I HAVE TRIPLE CHECKED ALL CONNECTIONS I MADE FROM THE BATTERY TO THE ADDED LIGHTS AND EVERYTHING IS FINE. THERE IS POWER GOING TO THE RELAY FROM THE BATTERY. I THEN UNHOOKED ALL OF THE ADD-ONS AND STILL NO FACTORY BACK UP LIGHTS. I HAVE TRIED EVERYTHING I KNOW TO TRY WITH NO SUCCESS. THE ONLY THING THAT HAS HAPPENED DURING ALL OF THIS TIME IS FUEL GOT ON THE TRANNY WHEN MY SEPARATOR LEAKED FOR ABOUT 2 WEEKS. WHADDAYA THINK GUYS? I AM AT WITS END AND ON A BUDGET. ANY AND ALL HELP OR SUGGESTIONS ARE GREATLY APPRECIATED !!!!!!!!!!!!!!

 

Have you checked the fuses and relay under the hood in the battery junction box? If you have trailer tow package you might have popped one of those.


Austin

 

The trailer tow fuses are # 1(7.5A) 3(7.5A) and 4(20A) mini fuses


Good luck,

Austin

 

THANKS AUSTINS, I CHECKED ALL MINI FUSES UNDER THE HOOD, THEY ALL LOOK FINE. I DON'T KNOW HOW TO GO ABOUT CHECKING ALL THOSE RELAYS. ACCORDING TO THE LIST OF ALL THE RELAYS IN THE OWNER'S MANUAL, THE TRAILER TOW RELAY SHOULD BE #38, BUT THERE IS NO #38 UNDER THE HOOD NOR ON THE LAYOUT PAGE IN THE BOOK SHOWING WHAT # IS POSITIONED WHERE. WHAT DO YOU MAKE OF ALL THAT???? THANKS !

 

This one turned out to be a bad switch assembly on the side of the transmission. I could get no response with a test light down under when my son set the park brake and held the brake pedal with the truck in reverse, so I went to the dealership and they replaced the switch.....ALL IS GOOD! Thanks for all the help! Sorry for taking so long to post the fix!

 

You need a relay
check this out
https://www.ford-trucks.com/forums/5...reverse+lights

 

Thanks khadma! I just went back tonight and posted the fix, it was the tranny switch, but thanks for the help! We must have passed each other in cyberspace! LOL