Was cruising into work yesterday am. Small herd of deer in the road and I was going to go around them when my truck hit a patch of ice and plowed into a large snowbank and sunk.

Got her out last night with a frontloader...she fired up and drove fine but I have no turn signals nor brake lights....went out and got under the dash but can't read any of the markings on the fuseblock to do any backtracking...anyone have a pic or the layout of the fuseblock for a 1991 D350?

edited* no blown fuses

Thanks!!!

 

Check under the frame rails at teh rear corners of the bed, you may have dislodged one of the connectors in teh wiring harness.
and both those ligths share aground wire, it is teh solid black in teh harness at the rear of the truck...

 

wouldn't that effect the backup lights and the parking lights? Those all work, it's just the turn and brake.

 

Is it just the rear turn and brake or is the front turn out also. Belive or not I lost both rear brakelights at the same time.

 

both rear brakes and all 4 turn do not work at all.

all parking lights work
backup lights work
guages all work
instrument cluster lights work
Horn,radio,cb all working fine.
overdrive switch, cargo light, and heater blower all work.

Checked the connections at the back of the bed and they are all tight.

This is frustrating....I have to drive home in the dark and it's approx 50miles one way....

 

Are you sure about the fuses?

Isn't there an underhood PDC and another fuse compartment in the interior of the cab?

 

Hazards work?

The hazards, brake lights, and turn signals are all fed off different fuses and fusible links. From looking at the wiring diagram, the one thing that could take them all out at the same time is the turn signal switch.

 

PDC??

Nope, hazards don't work either....come to think of it, I never tried them to begin with.

Made it home w/no tickets ..... thought that I was gonna get hit a couple of times though...

unplugged and re-seated the connections at the back of the rig...nothing.. Guess I am gonna hafta crawl under her...


BTW....getting a bunch of snow packed in the rims makes a 1 ton feel like a jackhammer........I thought I was gonna lose all my fillings......

 

PDC = Power Distribution Center.

The overvalver is trying to be helpful, but we don't have a PDC - unless you want to call that rat's nest of fusible links by the battery a PDC.

I would unplug the turn signal switch and plug it back in. If that didn't fix it I'd replace the switch. That is the only point where all these systems come together. If it was only the rear I could see the problem being under the truck, but the front signal wiring is totally separate from the rear wiring.

 

ok, I thought that is what he meant by PDC....I know that the 1st gens didn't use one.

Why would the turn signal switch affect the brake lights? I did go and replace the brake switch and no luck. I do have juice to the switch and after the switch.

I will dig into the column tomorrow....it's late and I am freezing...it's -3 right now.

Thanks for the help guys....will hit it again tomorrow.

 

The power from the brake switch goes through the turn signal switch to get to the lights.

Like I said - the only place all those systems come together is at the turn signal switch. Could be a bad connection, could be a bad switch. We know it's not fuses, and we know it's not fusible links because too much electrical stuff works.