I am in the process of putting new lights on the rear of my 1978 FJ40. The new lights have orange, red, and white lens. The red portion has 2 wires. My question is, how exactly do you wire these. Just want to know what each light is and how to wire. The previous owner cut the original wire harness out and added aftermarket taillights. Any help would be great. I have tried to find a easy to read wiring diagram, but haven't had any luck yet.
Need help with 78 FJ40 rear lights wiring!
- Thread starter AJSFJ40
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AJSFJ40, just went thru the same pain, replaced the uber-rusty housings that were jerry-rigged and the wiring chopped up by my PO.
If you still have the factory wiring in there or you paid attention when you chopped out the old, here's the original color code that I could decipher from the remains
Red/Blue wire goes to back up (white)
Green wire and Green/White wire go to brake (red) GW is for brake, GN is for running lights (i think)
Green/Yellow wire go to turn signal (yellow)
Good luck, this might not be 100%, but it's a start. My s*** was all f'd up
True Dat. My PO installed some aftermarket antenna, so I go to remove it to put an OEM antenna back on, and it looks like the PO just gouged a 3/4" hole in the sheet metal to install it
If you still have the factory wiring in there or you paid attention when you chopped out the old, here's the original color code that I could decipher from the remains
Red/Blue wire goes to back up (white)
Green wire and Green/White wire go to brake (red) GW is for brake, GN is for running lights (i think)
Green/Yellow wire go to turn signal (yellow)
Good luck, this might not be 100%, but it's a start. My s*** was all f'd up
True Dat. My PO installed some aftermarket antenna, so I go to remove it to put an OEM antenna back on, and it looks like the PO just gouged a 3/4" hole in the sheet metal to install it
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Got into the taillight rewire last weekend as well. I think phrogg4ever is right reqarding the colors, there's a nice wiring diagram in the tech section. I hope that I have them wired correctly, but still have some bugs to work through. The hazards only work correctly with the L turn signal on and the running lights still don't work no matter what I do. At least I've got brake lights, no one in FL uses a turnsignal anyway!
I've checked the fuses and grounded both taillights directly to the frame.
Any other suggestions are greatly appreciated.
I've checked the fuses and grounded both taillights directly to the frame.
Any other suggestions are greatly appreciated.
bought some taiwanese tailites from sor --looked good but wiring colors were all messed up. took a long afternoon to reconfigure one of them. these units look good though. also could not get the (i think it was the turn sigs) to work until i changed the included 5 watt bulbs to the original 25-30 watt bulbs. weird i know but i guess the flasher thingy is sensitive to resistance or something. only back ups don't work. will figure that later jim
yeh those flash cans only work when they have something to do... ie light up a bulb (i found that out after a very long weekend.)
and i dismantled my indicater switch at the stalk and made my own hazard light switch.. (a little bit technical but now i know know how it works so all good!
and madoc1... you back ups just work on a switch on the gearbox (have to take of hump to get to.. ) run one side of the switch to pos. and the other to your backups.. (put a fuse in there even though you globles kinda act like fuses carnt be to careful i rekon) just run new wires... so much easier..
and i dismantled my indicater switch at the stalk and made my own hazard light switch.. (a little bit technical but now i know know how it works so all good!
and madoc1... you back ups just work on a switch on the gearbox (have to take of hump to get to.. ) run one side of the switch to pos. and the other to your backups.. (put a fuse in there even though you globles kinda act like fuses carnt be to careful i rekon) just run new wires... so much easier..
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75 rear wiring problems
So I had no rear running lights or backup lights, but my rear turn signals worked fine. I took apart the tail lights, cleaned everything and relplaced the bulbs.
That didn't work so I went deeper and saw some PO wiring. In the process of tugging on wires my turn signals don't work.
MY QUESTION: where does the rear wiring harness enter cab? I see it run along the right side of the frame, but can't isolate its entry point.
Thanks,
adam
So I had no rear running lights or backup lights, but my rear turn signals worked fine. I took apart the tail lights, cleaned everything and relplaced the bulbs.
That didn't work so I went deeper and saw some PO wiring. In the process of tugging on wires my turn signals don't work.
MY QUESTION: where does the rear wiring harness enter cab? I see it run along the right side of the frame, but can't isolate its entry point.
Thanks,
adam
Passenger side bulk head.
Follow the harness along the frame rail and you will see where it leaves the frame and attaches to the body. There are two connectors where it attaches to the harness for the rest of the cowl.
Much thanks, I will let you know how it goes. Ohh, newbie mistake its a 75.
I also just ordered new tail lights, because one of the housings was pretty rusted and I believe it serves as the ground for the brake and running lights?
thanks!
I also just ordered new tail lights, because one of the housings was pretty rusted and I believe it serves as the ground for the brake and running lights?
thanks!
Tail light problems
Finally a forum that might get me some where. I will share what I have been dealing with and maybe it will help someone here. 1977 FJ40, decided to replace the tail lights a few weeks ago. Bought from SOR. Installed them and remade a lot of the rear harness. All lights worked, backup, (white), brake and parking, (red) and turn signals, (yellow). Only problem I had was the turn signals flashed very fast. Hazard lights flashed slow and normal. Noticed that there was an additional wire attached to the spring behind the yellow bulb that was cut. I added a wire to the spring and ran it to ground and they still flashed fast. I had not dressed and tidied up the new harness yet and this ground wire touched one of the wires going to my side markers or license plate lamps. What this essentially did was kill all my parking lamps and dash lights. Replaced the blown fuse. Brake, backup, and turn signals still worked, albeit fast still. Just no parking lights. So now I am thinking I fried a brand new light switch. Took it out bypassed the wire and the headlights still worked fine. Bypassed the wire and the parking lights still did not work. Duh, accidentally touched one of the studs on the back of the gage cluster to the dash opening and now the turn signals, hazards, dash, and parking lights don’t work. Flasher relay stopped clicking. Replaced every fuse in the fuse panel. Turned out the light and quit before I did something irrational with a shotgun. I will try the higher watt bulb that madoc1 mentioned. Of course after I replace the flasher relay that I think I fried. Any and all suggestions would be helpful and tried. Still have three feet of snow on the ground in northern New Hampshire so I have another month to figure it all out. Thanks
Finally a forum that might get me some where. I will share what I have been dealing with and maybe it will help someone here. 1977 FJ40, decided to replace the tail lights a few weeks ago. Bought from SOR. Installed them and remade a lot of the rear harness. All lights worked, backup, (white), brake and parking, (red) and turn signals, (yellow). Only problem I had was the turn signals flashed very fast. Hazard lights flashed slow and normal. Noticed that there was an additional wire attached to the spring behind the yellow bulb that was cut. I added a wire to the spring and ran it to ground and they still flashed fast. I had not dressed and tidied up the new harness yet and this ground wire touched one of the wires going to my side markers or license plate lamps. What this essentially did was kill all my parking lamps and dash lights. Replaced the blown fuse. Brake, backup, and turn signals still worked, albeit fast still. Just no parking lights. So now I am thinking I fried a brand new light switch. Took it out bypassed the wire and the headlights still worked fine. Bypassed the wire and the parking lights still did not work. Duh, accidentally touched one of the studs on the back of the gage cluster to the dash opening and now the turn signals, hazards, dash, and parking lights don’t work. Flasher relay stopped clicking. Replaced every fuse in the fuse panel. Turned out the light and quit before I did something irrational with a shotgun. I will try the higher watt bulb that madoc1 mentioned. Of course after I replace the flasher relay that I think I fried. Any and all suggestions would be helpful and tried. Still have three feet of snow on the ground in northern New Hampshire so I have another month to figure it all out. Thanks
Electircal problems suck
So I had to get my FJ inspected asap, which meant I had to fix the rear brake lines and all the lights and turn signals.
About 30mins into the job I "killed" the turn signals trying to fix the rear running lights. HAHA.
So I took the night off, got up early and bought an optima battery and new leads. Now this thing turned over like a virgin on prom night! I bought new rear light set up from SOR and went to work.
Then it started to rain...did I mention I have to do this outdoors. Didn't matter, I had a date with the inspector. So after fixing the Mickey Mouse wiring the PO had done by a crappy shop the rear's were working.
Now only the front side (facing L & R) turn signals worked (75) but not the turn signals facing oncoming traffic. I tested the wires and power was coming to both. I replaced the bulbs and nada. Then for some reason I placed the smaller side bulb in the front and they blinked away. CAN ANYONE EXPLAIN THIS?
Thanks,
Adam
75 FJ
So I had to get my FJ inspected asap, which meant I had to fix the rear brake lines and all the lights and turn signals.
About 30mins into the job I "killed" the turn signals trying to fix the rear running lights. HAHA.
So I took the night off, got up early and bought an optima battery and new leads. Now this thing turned over like a virgin on prom night! I bought new rear light set up from SOR and went to work.
Then it started to rain...did I mention I have to do this outdoors. Didn't matter, I had a date with the inspector. So after fixing the Mickey Mouse wiring the PO had done by a crappy shop the rear's were working.
Now only the front side (facing L & R) turn signals worked (75) but not the turn signals facing oncoming traffic. I tested the wires and power was coming to both. I replaced the bulbs and nada. Then for some reason I placed the smaller side bulb in the front and they blinked away. CAN ANYONE EXPLAIN THIS?
Thanks,
Adam
75 FJ
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Do yourself a favor and trust me it will work. Do what i did. I was chasing my tail for weeks after replacing all my lights trying to get them to work properly. Here is what fixed it. Remove your fuse panel and lower it so it is accesable. Disconnect battery first of course. Take out all the fuses and take a 1/4 inch diameter file and file all the fuse sockets. They are brass and tarnished and not making good contact. If i did this first i would have gone to bed a few nights less pissed off. I swear every single light worked. Just make sure you have 24-28 volt bulbs in the turn signals because they work on resistance.
thecrazygreek
A.K.A. TheCraftyGreek
What I find interesting is that you need some high watts to get the lights to blick. Too much wattage and they blink faster... Too little wattage and no blinky...
I have a 76 FJ40 and found that 30-40 watts kicked in the flasher and made them blink. So I installed two 20 watt bulbs (front and back) in the signal area (front clear upper part of the three way) and in the yellow area of the rears...
Wiring is fun! 32 year old vehicles can have a HUGE assortment of PO rigging. Some good, some not so much...
I have a 76 FJ40 and found that 30-40 watts kicked in the flasher and made them blink. So I installed two 20 watt bulbs (front and back) in the signal area (front clear upper part of the three way) and in the yellow area of the rears...
Wiring is fun! 32 year old vehicles can have a HUGE assortment of PO rigging. Some good, some not so much...
Can anyone explain why when I step on the brake pedal, my right rear brake light and my front left turn signal light up? All lights work normally outside of this one issue.
Check your brake bulb , you might have the wrong type, you need a 2 filment bulb. That is 2 contacts in the bulb's ass.
