My buddy was hooking up his boat to my truck thismorning and when he hoked the lights up, there was a pop and the dash lights as well as the rear running lights went out. the break lights and turn signals work but not the running lights.

Im going to try to replace the bulb and see if that works for the rear.

Does any one know if the dash lights going out could be a fuse? and if so which fuse would that be?

 

Check the owners manual. It should have a complete fuse map

 

How did that happen, the factory trailer tow adapter uses different fuses for the parking lamps.

 

Im reading through the owners manual and all the fuses appear to be okay.. would a bad relay be a problem?

and i have no idea how this happened. I know nothing about eletrical so its a shot in the dark.

 

What does "appear to be okay" mean ?

When you put the meter on one side and get power, do you get the same reading on the other side ?

The fuse that should have blown when hooking up the trailer is BJB ( aka Battery Junction Box, Engine Compartment fuse panel ) Fuse # 5

The fuse for the truck's parking lamps is BJB Fuse # 6
The instrument illumination fuse is CJB ( aka Central Junction Box, cab fuse panel ) fuse #18 ( which only has power when the main headlamp switch is in the park or head positions ).

The circuit from BJB Fuse #6 triggers the trailer tow adapter parking lamp relay.

This is the question I had on how did this happen, the trailer tow adapter parking lamps are isolated from the truck's parking lamps.

Is this really a factory trailer tow adapter ?

Go back and test the fuses with a good / no good answer, not an appear to be type answer ( that is about as useful as 'I think' ).

 

When i checked them, i just pulled them out and looked to see if it was burnt. But after i finally used the circut tester, i realized that the #5 fuse under the hood was bad and the #18 under the dash was bad.

I honestly dont know how it happened, when the trailer lights got plugged in, all the others went out.

I should have just used the tester in the first place but i wasnt thinking. thanks for yalls input

 

maybe the trailer brake light electrical system has a short

 

You've been to school today my friend and Scully was your teacher (and a darn good one). Remember what he taught you about fuses (and the testing of them). It will serve you well in the future.