Headlights working and now not working *76 FJ40* :/ (1 Viewer)

[gmr76]

New to me 76 FJ40.

Headlights worked no issues until yesterday. I went out for a walk with my kid and since he was asleep when I got back I took advantage of the few extra minutes and swapped out the old turn flasher with a new one. Tested flashers - they worked, got kid up and went along with my day.

Went last night to run to the store and when I went to turn the headlights on i got only side markers in both positions. No headlights (low or hi).

Turns signals work... side markers work... but no headlights.

Wiring is a little wonky on this truck thanks to PO... but wanted to come here to see if anyone had a place to start before I start pulling things apart.

I have looked through FSM and the wiring diagrams... unfortuanly car electronics are not my thing.

Thanks in advance.

 

[pb4ugo]

Make sure the fuse is in contact with both the fuse holder clips. I've had to slide the fuse back and forth within the clips more than I can remember. You might disconnect the batt and remove all the fuses and use a wire brush to clean the contacts. I use something like a .22 cal cleaning brush. I've also have had to pull the headlight switch in and out to try and clean the contacts within the switch.

 

[45Dougal]

Yea sounds like the headlight fuse - since it's new to you I'd replace all the fuses with the correct values, and stock up on a few spares. Clean up the contacts as mentioned.

The vibration kills them; a lot of mine wind up with the filament breaking away from the end cap - so they look OK but are intermittent.

 

[South Texas 97]

Just to clarify, on an FJ40, it’s auto electrics, very little electronics involved
the wiring diagrams are fairly straightforward, I copied mine onto 11x17 and made like 4 copies, and on at least two of them, write notes all over them.
A simple 12v test light, and a cheap multimeter are the tools you need.
I second the idea of removing the fuses, and using a small round brass brush to clean the contacts, and then check the fuses themselves , or even replace them all, they are not expensive.

 

[charliemeyer007]

+1 for enlarged copy of wiring diagram. I had it blown up to A2 size (16x24) and then laminated back in the 80's - still a pleasure to work with. Elsie sat since before 2010, until a few weeks ago. Had to replace the electric fuel pump and file the points to get her to fire up. After idling a while the charge indicator started working. I think the front heater fan works and I have one brake light that stays on. So after I sort out the brake issues, maybe the carb and dizzy I'll start on the wiring. New clutch master, slave and ss hose are wonderful.

I keep a CCI 100 pack plastic case full of the correct size fuses in the glove box along with one of the poke in the wire test lights with several extra bulbs. A 30 cal bore brush work nicely in the fuse clips

 

[45Dougal]

+1 for enlarged copy of wiring diagram. I had it blown up to A2 size (16x24) and then laminated back in the 80's - still a pleasure to work with. Elsie sat since before 2010, until a few weeks ago. Had to replace the electric fuel pump and file the points to get her to fire up. After idling a while the charge indicator started working. I think the front heater fan works and I have one brake light that stays on. So after I sort out the brake issues, maybe the carb and dizzy I'll start on the wiring. New clutch master, slave and ss hose are wonderful.

I keep a CCI 100 pack plastic case full of the correct size fuses in the glove box along with one of the poke in the wire test lights with several extra bulbs. A 30 cal bore brush work nicely in the fuse clips

+1 for large format laminated diagram.
You can update it with marker pen when you discover that your wiring isn't quite as it left the factory. Then you can rub them off again when you get it back to what it should be.

 

[peesalot]

Check the foot switch if 76 had one ?

 

[gmr76]

I went and grabbed my .22 cleaning brush and cleaned the fuse clips and we had some success. I have lights maybe 9 out if 10 times I put the switch out. Better than no lights but I’ll keep poking around! Thanks for the replies

 

[77mustard40]

Your on the right track, I’ve had that issue with my 77 and a solid cleaning of the fuse clamps solved the issue

 

[rsrai]

I found mine turn on every other time I’d pull the switch, found when I jiggle the switch if turns on so need to clean up the switch connections.

 

[fjwagon]

I always say, reseating and cleaning connectors is always a good start. It usually clears the the problem. Same with grounds. They tend oxidize over time.

 

[Engineer8000]

The connectors on the back side of the fuse block can get corroded also. The headlights draw a lot of current so a loose connection will get hot.