[vvrustbucket]

Hello all. I am a complete newbie so bear with me please.

Three months ago I bought a 1977 fj40 from an older guy who just ripped through rivers etc. It was $450, so I assumed plenty of work would be needed. I now have it idling fairly well, so I thought I might try and hook up turn signals and tail lights. I was able to salvage one original turn signal, but bought cheapie tail light combos and one turn signal.

Now, after spending ten hours or so I thought I was making progress. I got the fronts to work, although not blinking. ( do I need to have all four lights up and running before they blink or I guess it could be the thermal flasher's gone bad?) Ok, next I gerry rig the 4 wires meant for original tail light assembly and connect them to the 3 wires that the tail light I bought had. The lights kind of worked but were very dim( I assume this is a result of combining wires).

Now here's the kicker. I step on the brake pedal and the front turn signal illuminates! Wiring problem? Ground problem? Newbie problem? Probably all three! I just laughed at myself for 25 minutes then turned off the lights and called it a day.
Any help or advice could be used, maybe I'm the only person finding this funny but it cracked me up! Thanks

[mel lowe]

you have a ground issue

[HAMBURGLAR11]

ditto

[KOOTENAY KRUZER]

Turn signal needs at least 2 bulbs working on a side before it will flash that side. Dead bulb or bad ground equals no flash.

Toyota wiring for tail lights uses a separate bulb (or at least filament) for each function (brake, tail, turn, backup) and domestic combines brake and turn signal. If the combos you used were meant for domestic vehicles you just wired the front signals to the brake light switch.

[D'Animal]

Did someone mention a bad ground?

[vvrustbucket]

Ok, so bad ground, is it something where it requires rough sanding or am I talking getting out the angle grinder and exposing a complete new section of bare metal? Or are we talking the wires are hitting somewhere else along the line and that's making a bad ground?

I looked at the light combo and it looks like it's for mostly domestic vehicles, but the first listed is £eep( didn't know if that was a bad word here) so I thought it might work. Can anyone help me learn about reading these wiring diagrams. I see it as the wires that are

Solid green = tail light
Green white = brake light
Green yellow = turn
Red(mines blue) = back up light?

Thanks again for reading and helping

[Copenhagen1]

The best advice on wiring that I read on this forum was to take the fuse block out, unplug the wires from the back, take the glass fuses out of the blade holders and take a small round file and clean up the contacts where the fuses touch the blades. Also check the continuity of each fuse before you put it back in. Try to shine up the contacts where the plugs go into the back of the fuse block also.

Your contacts are 30 years old and could probably stand a polishing.

I also agree with everyone else that it is a ground issue but I would do the above mentioned maintenance before proceeding to anything else.

Oh, and by the way, Welcome !

Copenhagen1

[Vicm]

Originally Posted by vvrustbucket

Ok, so bad ground, is it something where it requires rough sanding or am I talking getting out the angle grinder and exposing a complete new section of bare metal? Or are we talking the wires are hitting somewhere else along the line and that's making a bad ground?

I looked at the light combo and it looks like it's for mostly domestic vehicles, but the first listed is £eep( didn't know if that was a bad word here) so I thought it might work. Can anyone help me learn about reading these wiring diagrams. I see it as the wires that are

Solid green = tail light
Green white = brake light
Green yellow = turn
Red(mines blue) = back up light?

Thanks again for reading and helping

What type of tail lights are you using?
If these are trailer type with the same bulb doing both brake and signal, you need a converter.
The stock wires should be green/blk LH signals, and green/yel RH signals for a 77.
Green/W stop light , Red/Blue backup lights, and green for park lights.
If you have side marker a white/blk is used for grounding them.
The ground is done through the screws that fasten the stock taillight assembly to the crossmember.
So the first step is to use your tester and see if the wires in your 40 are intact functional and in agreement with the wiring diagram.
Then figure out if the taillights that you want to use are compatible with the 40 wiring. Then wire them up.
The flasher will flash as long as you have 2 bulbs connected in parallel and in series with the flasher. So when you test the signal wiring the tester light will be solid unless another bulb is also getting power from the flasher.

Vic

[D'Animal]

There are grounds all over your rig.

Body to frame.

Body to engine

Engine to frame.

Many times it is redundant (sp?) meaning you may have two grounds going from the body to the frame in differnt locations, etc.

[vvrustbucket]

well another productive day, I did clean the fuse box and reinstalled it, everything seemed to work. I then also was able to get one side blinking, so that was thrilling. The other side is giving me fits, but I'm going to try to struggle through, thanks to all for their info!