Robert m

iTrader: (2)

back in dec. my factory alternator started overcharging so i replaced it with a napa rebuild. so on this past saturday my new alternator also started over charging to around 18v. i got the truck home and swapped the alt out on sunday. once i got the new one in it was charging at 12.3v at the battery so i knew something was up. i probed the alternator stud and was getting just under 13.7 there so i knew i had a problem in the wiring between the alt and battery. i ended up tracing the wiring down and found the main 80 amp alt fuse in the fuse box had melted (not blown) along with the fuse holder. the wire was also nice and crispy. i got a new fuse and holder from the junk yard and while at it, took the time to run a new 4ga wire from the alternator to the battery. got it all back together today and it fired up with no issues and charging 13.8v at the alt and 13.7 at the battery. but now i just noticed while moving it back into the garage that i have no running lights front or back, no gauge lights, no brake lights and when the key is turned to the on position, the only light i get is the battery light. the headlights, blinkers, hazards, wipers, radio, horn, cig lighter and dome light all still work. i checked all the fuses and they all seem to be good.
so my question is, WTF is going on? im stumped, big time on this one.

crazypaint

Maybe a relay got fried also

Robert m

iTrader: (2)

is there a relay that controls the running and other lights? if so where is it located?

Robert m

iTrader: (2)

anybody?

Patriot

Are you sure the new fuse box is correct?

Robert m

iTrader: (2)

i didnt replace the whole box. just the melted holder, wire, and 80a fuse.

crazypaint

Ill have to look at mine again and ill get back to you

Robert m

iTrader: (2)

pulled the fuse box in the cab because the gauges fuse terminals were loose and the fuse wouldnt stay in place. thought it might have gotten hot and melted. pulled it apart and all looked well inside and i fixed the loose connection and now i have all the warning lights again.
checked the tail light relay and am getting no power to any of the terminals. along eith nothing at the brake and blinker fuse.
getting closer but ga'daum i hate trucks...

Robert m

iTrader: (2)

so i replaced the interior fuse box and the relay integration module in the back of it but still no change. does anyone know if the brake light circuit runs through the blinker combo switch on the steering column?

wyoming9

iTrader: (1)

I would look and make sure all the fuses are making a good connection in the fuse block.

Even if the fuse is good a bad connection is just like having a blown fuse.

Brake lights are just brake lights from the fuse to the switch.

Electrical issues are bad but without the wire diagrams even worse

The tail light relay gets power from the 80amp fuse did you miss a connection or is a wire burnt you just did not see.

Just try and get one circuit at a time if your looking to get them all at once just make sure there is no flammable liquids near by it is to tempting

Robert m

iTrader: (2)

OK I GOT IT!!!!!!
just a future reference for anyone doing the big 3 upgrade or replacing your factory alternator wire, make sure you splice in BOTH wires that come off the main alternator wire. there is one on the drivers side and one on the passenger side that T off. i missed the one on the drivers side and cut the factory wire out right before it. it is what was causing all my power loss issues.