1979 FJ40 headlight switch drama! (8 Viewers)

[Atlas Suspension]

I know this topic has been here before, but I did a search and couldn't find the relevant info so here it goes here:

A couple of years ago my headlight switch started acting up, I'd pull it apart and put it back together, it would work for a couple of days/weeks then when I'm driving down the freeway no more headlights. I looked for a proper replacement and there were none to be found that weren't ridiculously over the top expensive. I got pissed and ripped the thing out and wired up a cheese Daystar light switch and carried on.

Finally stumbled across one that looked right and horse traded some parts and cash for it, it sat for a couple of months while my truck was down and last night I ripped out the cheesy switch without looking at what was what, plugged it in and VIOLA! It doesn't work properly. The first setting gives me headlights and cluster (dimmer works) and the second gives me….. everything else. Needless to say I am pretty bummed.

I called SOR today and came to the conclusion that I have a 73-77 (I think?) switch and that the wiring was different.

Does anyone have a diagram of a pre 77 AND a 79-82 that I can compare so that I can wire up some pigtails and get this thing working? The switch I got is a nice piece and I don't want to have to rewire that cheesy switch. If no diagrams is anyone familiar enough with that headlight harness to be able to tell me what I'll have to cross to make the thing work right? All of the parts are there, and I know I can figure it out again, like a dumbass I tore the wires out from the cheesy switch and have since forgotten what was what and I'd like to skip the hassle of learning the whole thing again. Any help would be appreciated!

 

[antFJ]

You are correct. My switch is from a 77 and my harness is a 78. I always pull my switch out to the furthest setting so it doesn't bother me much. I'm pretty sure you can re - arrange the wires in the switches plug to make it work correctly

With a multimeter it shouldn't be too difficult. Just figure out which wire does parking lights and which does the headlights and switch them

 

[bj40green]

Here are some pics from the FSM. Hope this helps.

.

Rudi

 

[Atlas Suspension]

Here are some pics from the FSM. Hope this helps.
View attachment 893886 .

View attachment 893885

Rudi

That will be a huge help! What year switch is on that? Thank you so much! Any chance anyone has both vintage FSM's to line them up? This will come in handy not just for myself, I had a friend going through the same thing a couple of years ago.

 

[bj40green]

Download FSM 98127 1972 -1974:
https://drive.google.com/file/d/0BwGk8zcL34N4R01acFVTVmh6MWc/edit?usp=sharing

Download FSM 98154 1975 - and later
https://docs.google.com/file/d/0BwG...ZjFkLTg4YmYtMjRmMGIxZTQ0MmQ2/edit?usp=sharing

Rudi

 

[antFJ]

you jinxed me! My headlight switch just stopped working. I'm going to have to disassemble and rebuild it this weekend. While I have it out I will see if I can re-wire it and post up how to make an earlier model light switch work with a later model truck

 

[Atlas Suspension]

Download FSM 98127 1972 -1974:
https://drive.google.com/file/d/0BwGk8zcL34N4R01acFVTVmh6MWc/edit?usp=sharing

Download FSM 98154 1975 - and later
https://docs.google.com/file/d/0BwG...ZjFkLTg4YmYtMjRmMGIxZTQ0MmQ2/edit?usp=sharing

Rudi

Fantastic info! Don't know how I missed these.

you jinxed me! My headlight switch just stopped working. I'm going to have to disassemble and rebuild it this weekend. While I have it out I will see if I can re-wire it and post up how to make an earlier model light switch work with a later model truck

Aww man! I feel your pain. I'm over the electrical demons! I was planning on putting something together this weekend as well! If I get it together we can compare what we have. I'm about to post another thread about another electrical issue I'm having…. gotta nip this crap in the butt.

 

[antFJ]

rebuilt my switch and swapped the wires in the harness... waiting to get a BA7 light bulb in the mail for the switch before I install it back in... pics to show you what to do shortly...

rebuilding the switch was pretty straight forward... undo the little clasps with a small flathead screw driver and everything comes apart. don't lose the little springs or ball bearings. I cleaned everything up and then used a healthy amount of white lithium grease. I hit all the contacts with emory cloth (fine sandpaper). Here is how to make a 78 and later harness work with a 77 and earlier switch.

use a paperclip to hold down the tab that keeps the terminal in the connector and then pull on the wire from the back to pull the terminal out. The bottom two on the outside of the connector need to be switched.... that's it!

 

[Atlas Suspension]

rebuilt my switch and swapped the wires in the harness... waiting to get a BA7 light bulb in the mail for the switch before I install it back in... pics to show you what to do shortly...

rebuilding the switch was pretty straight forward... undo the little clasps with a small flathead screw driver and everything comes apart. don't lose the little springs or ball bearings. I cleaned everything up and then used a healthy amount of white lithium grease. I hit all the contacts with emory cloth (fine sandpaper). Here is how to make a 78 and later harness work with a 77 and earlier switch.

use a paperclip to hold down the tab that keeps the terminal in the connector and then pull on the wire from the back to pull the terminal out. The bottom two on the outside of the connector need to be switched.... that's it!

View attachment 895516 View attachment 895517

Aww dammit you beat me to it! I was all excited because I thought I'd be able to finally contribute meaningful info!! Yep... Switch the last two on that row of three and everything works like it was made that way! I made a fancy little harness from some wires and connectors with the plastic clip from my other switch and tucked it all up in there. No more ugly daystar headlight switch, although I'm sure I'm the only one that noticed.

Special thanks to antFJ and BJgreen for the contributions.

 

[Bripars40]

Okay so I'm having issues with my '79 headlight switch as well. The '79 switch will not turn on the headlights but it will operate the marker lights and turn signal lights.

I grabbed a spare switch from a '76 and it turns on the headlights but non of the marker lights.

Can anyone help me understand why my '79 switch isn't turning on the headlights?

 

[Bripars40]

Oh and my brake lights are not working... haven't checked the bulbs but thought it might be related since they worked several months ago.

 

[Cfrost]

Download FSM 98127 1972 -1974:
98127 chassis-body '72-'74.pdf

Download FSM 98154 1975 - and later
98154 chassis-body '75-'80.pdf

Rudi

thank you SO MUCH. This is going to help immensely. The haynes diagram is probably more harmful than helpful.

 

[Ivan Flores]

Okay so I'm having issues with my '79 headlight switch as well. The '79 switch will not turn on the headlights but it will operate the marker lights and turn signal lights.

I grabbed a spare switch from a '76 and it turns on the headlights but non of the marker lights.

Can anyone help me understand why my '79 switch isn't turning on the headlights?

Did you ever get a response to your question? I have the same problem!

 

[Bripars40]

Took the headlight switch apart and cleaned everything included a little fine grit sand paper to the copper contacts.

The taillight issue was resolved with a new ground at the taillight and patching some shoddy wiring by the PO.

Did you ever get a response to your question? I have the same problem!

 

[mtn biker]

Took the headlight switch apart and cleaned everything included a little fine grit sand paper to the copper contacts.

The taillight issue was resolved with a new ground at the taillight and patching some shoddy wiring by the PO.

how did you get the switch apart and remove it from the dash? i am working on a 78 that is having the same problem. ( my own 69 is much easier electrically ). this 78 is originally from New Jersey and there is corrosion everywhere and half of the wires are hacked and chopped in half.

 

[Bripars40]

how did you get the switch apart and remove it from the dash? i am working on a 78 that is having the same problem. ( my own 69 is much easier electrically ). this 78 is originally from New Jersey and there is corrosion everywhere and half of the wires are hacked and chopped in half.

Use this link to remove the knob:Removing dash knobs

Then I bent the four or six metal tabs that hold the two pieces of the switch together to gain access to the copper contacts. Then clean and rescuff the contacts. I would reconnect the switch to the wiring harness before reinstalling into the dash to make sure it all works correctly. I hope that makes sense.