tail light issues (1 Viewer)

[Paraglider]

I've got an HJ47. It was owned by a farmer before and he didn't care what worked as long as the thing ran and could haul and hold equipment, so I've got a few issues to resolve. One is my rear lights. The hazards work, the blinkers work, one brake light works (right side). No rear lights turn on when I turn on my headlights. So I'm trying to figure out why the other brake light doesn't work and why the tail lights don't go on when I turn on my headlights.

I went under, looked at the connections at the rear, took them apart, and see nothing amiss on the side the brake light works but a red wire has apparently become disconnected on the other (is that the brake light?). Here are some pics. They were all really dirty and still need to be cleaned.

Does anyone know what size wire these would be. I might need to add to the red wire.

Thanks for any help.

The one where everything works except the tail light doesn't come on with the headlights. Not sure what is in the black box the one larger black wire goes to.

Wondering what the two metal prongs are for that are covered in grease (was covered with tape)

The one with the cut/disconnected red wire. There are red, white, brown and black wires. I assume the black is the ground.

 

[Splangy]

It doesn't look like he cut the factory harness. I would just buy a set of god quality aftermarket tail lights and plug them in.

 

[sggoat]

X-2,---but the grounds are usually the issue with these--make sure each bulb has a good ground. I ran individual grounds for each bulb(front/rear/side marker/stop)--no issues in the last 6 yrs

 

[Paraglider]

It doesn't look like he cut the factory harness. I would just buy a set of god quality aftermarket tail lights and plug them in.

What do you mean "didn't cut the factory harness"? So is your thinking that because some of the lights work, there is probably not a problem with the electricity coming to the light and so the problem must be the lights, themselves? From what you can tell by the pics, is this a LED tail light or one with bulbs?

Also, an update on what I know: I tested for juice to the tail lights (brakes, blinker, hazards and tail lights). As expected given what I already knew, everything was good. The red cut wire and the green wire (you can't see in the photo) if connected allow the brake light to work, so both brake lights will be working once I find some extra wire to join those two wires. However, in the connector that is attached to the wires going back to the battery eventually, there is no juice to the single prong in the white connector. I am assuming this is the one that is related to the tail lights not coming on when I put the headlights on. Same story for both left and right sides and connectors. However, I'm not sure I'm testing it correctly as there is only one prong coming out, so I'm just putting the hot to it and the ground to the chassis. Is that correct?

All fuses are good, even the one where the fuse cover says "Tail." So I am assuming the problem is between the fuse and the connector somewhere but have no idea where it could be. That's where I hope some of you experts can help me.

the other thing, but I think it's just a "by the way" issue, is the tail light component is not the factory set up one. It is not white on the outside, then red and then orange. It is red, red and orange. I assume this wouldn't have anything to do with it since the issue seems to be no power to the connector the tail light fixture attaches to.

I've tried to read the electric schematic but I can't tell anything from it about where the source of the problem is.

Please help!

 

[Solace in Solitude]

I'm out in the bush and ran into a hot spot (cell connectivity)... I will likely be slow to respond, but... what year is your HJ47?

Your wire colors don't match any OEM FJ40 colors - Assuming an HJ47 has the same factory colors... so, the PO has done some wiring on the taillights... that what @Splangy meant by "didn't cut the harness"... but, the PO may have cut the harness upstream somewhere, I don't see anything in your pictures that look like factory colors.

For my '78 FJ40, the following colors apply... your's should be similar:

Green = Tail/Marker lights
Green-White = Stop lights
Green-Yellow = Right Turn
Green-Blue = Left Turn
Red-Blue/purple = Backup Lights
White-Black = Ground

The taillight harness joins the main harness at two connectors on the firewall (passenger side), a 3-pin and a 6-pin... if you check the colors at those connectors, they should match your schematic. The taillight harness runs down the firewall and thru the passenger frame-rail, to the rear... there are a couple of wires that branch off at the tranny (Backup Lights switch and Throttle Position Switch) and the fuel sender branches off right
around the same place and runs to the tank.

The PO has connected the colors you show to the rear harness, at some point. I would want to find this connection point and work it from there.

I'll check back when I have connectivity again, but I'm sure someone will help before then.

HTH

 

[Paraglider]

I'm out in the bush and ran into a hot spot (cell connectivity)... I will likely be slow to respond, but... what year is your HJ47?

Your wire colors don't match any OEM FJ40 colors - Assuming an HJ47 has the same factory colors... so, the PO has done some wiring on the taillights... that what @Splangy meant by "didn't cut the harness"... but, the PO may have cut the harness upstream somewhere, I don't see anything in your pictures that look like factory colors.

For my '78 FJ40, the following colors apply... your's should be similar:

Green = Tail/Marker lights
Green-White = Stop lights
Green-Yellow = Right Turn
Green-Blue = Left Turn
Red-Blue/purple = Backup Lights
White-Black = Ground

The taillight harness joins the main harness at two connectors on the firewall (passenger side), a 3-pin and a 6-pin... if you check the colors at those connectors, they should match your schematic. The taillight harness runs down the firewall and thru the passenger frame-rail, to the rear... there are a couple of wires that branch off at the tranny (Backup Lights switch and Throttle Position Switch) and the fuel sender branches off right
around the same place and runs to the tank.

The PO has connected the colors you show to the rear harness, at some point. I would want to find this connection point and work it from there.

I'll check back when I have connectivity again, but I'm sure someone will help before then.

HTH

Maybe they don't match the OEM FJ40 (assuming they are the same as the HJ47) because the tail light assembly isn't the stock. Instead of white, red and orange, it's two reds and orange. Maybe the PO got them from a nonLC source or something. Tomorrow, when it's light, I'll see if I can see those two other connectors on the firewall to test for juice. When you say "passenger side," are you referencing a RHD or LHD. Mine's a RHD cruiser and the lines I've seen pass on the driver's side inside the frame. The wire connector the tail lights hook to appears to be the normal one (two prongs one one side, two in the middle but separated more and then one prong only on the other side)

 

[DSRTRDR]

none of the pics you posted show factory wires - so, our comments are as good or bad as your own guesses

 

[Splangy]

none of the pics you posted show factory wires - so, our comments are as good or bad as your own guesses

The factory tail light connectors are clearly visible in the photos.

 

[DSRTRDR]

with a lot of dirt to obscure colors no less

 

[bj40green]

FYI

What you have there is an aftermarket (maybe LED) tail light unit with non matching colored wires.
You can find the wire colors in the FSM that I've sent you earlier.

Rudi

 

[Coolerman]

Folks bear in mind that Toyota, for reasons unknown at this time, did NOT use the colors shown on the schematics in the rear chassis harnesses starting sometime in 1976 or 1977.
The rear colors Toyota used are as follows:
Red = Left Turn
Yellow = Right Turn
White or Gray = Brake
Green = Tail
Red/Blue = Reverse

Those must be LED lights as that black finned thing is a load resistor. If you use an LED flasher you don't need the resistor...

 

[Paraglider]

Wow! Thanks for all the info everyone and for the pics with explanations, Rudi. Now I know better what's going on with the wires.
On the connector that comes from the battery side, there are two sets of two prongs, the one in the middle more separated than the other, and only one prong with a hole across from it as if there could have been a second prong (but not made with it). What is that about and is that the one that connects to the tail light to explain why the other lights are working but not the tail light?

 

[bj40green]

Folks bear in mind that Toyota, for reasons unknown at this time, did NOT use the colors shown on the schematics in the rear chassis harnesses starting sometime in 1976 or 1977.
The rear colors Toyota used are as follows:
Red = Left Turn
Yellow = Right Turn
White or Gray = Brake
Green = Tail
Red/Blue = Reverse

Those must be LED lights as that black finned thing is a load resistor. If you use an LED flasher you don't need the resistor...

Hmmmmm, @Coolerman are you talking about FJ40's USA market? Because my '78 BJ40 GENERAL market has the colors as per the FSM (all green with stripes). We (Paraglider) are talking a HJ47 here.

Rudi

 

[Coolerman]

Yes, sorry Rudi, I was referring to the USA spec Toyota. It can get confusing sometimes keeping track of what truck a thread is referring to!

 

[Paraglider]

I'm out in the bush and ran into a hot spot (cell connectivity)... I will likely be slow to respond, but... what year is your HJ47?

Your wire colors don't match any OEM FJ40 colors - Assuming an HJ47 has the same factory colors... so, the PO has done some wiring on the taillights... that what @Splangy meant by "didn't cut the harness"... but, the PO may have cut the harness upstream somewhere, I don't see anything in your pictures that look like factory colors.

For my '78 FJ40, the following colors apply... your's should be similar:

Green = Tail/Marker lights
Green-White = Stop lights
Green-Yellow = Right Turn
Green-Blue = Left Turn
Red-Blue/purple = Backup Lights
White-Black = Ground

The taillight harness joins the main harness at two connectors on the firewall (passenger side), a 3-pin and a 6-pin... if you check the colors at those connectors, they should match your schematic. The taillight harness runs down the firewall and thru the passenger frame-rail, to the rear... there are a couple of wires that branch off at the tranny (Backup Lights switch and Throttle Position Switch) and the fuel sender branches off right
around the same place and runs to the tank.

The PO has connected the colors you show to the rear harness, at some point. I would want to find this connection point and work it from there.

I'll check back when I have connectivity again, but I'm sure someone will help before then.

HTH

Okay, I finally had time to look at this and clean the wires. Here's what I have for the connector wires on the right tail lights where everything works except the tail light. The colors correspond to what you tell me except for one:

black and white (so ground) This is connected to a bigger gauged white wire and also a black one that goes to the resistor.
green (so tail light) This one is connected to a red wire on the light side and it appears to work the stop light from what I recall, not the tail light, but I'll double check.
green and white (so stop lights) This one is attached to a yellow wire. Don't remember what this works; will have to rehook it and test.
green and yellow (so right turn) This one is connected to a brown wire. Will have to reconnect to see what it works.
red and blue (so back-up lights) Never tested whether the back-up lights worked. Will do that.

 

[Paraglider]

Hope you guys haven't given up on me. Been sick, plus the holidays, but I do need your input as follow-up. in the meantime, I bought OEM tail light fixtures to get away from all the different colored wires on those LED ones and get it back to the original look. Same result, though--blinkers and stop lights work (keep forgetting to ask someone to get out and look to see if the back-up lights work) but the tail lights and license plate lights don't (which, according to the schematic, seem to be connected to the same source). I followed Pngunme's advice and looked to find the wires at the firewall. I found the six-pin one but there was no 3-pin wire connector, just a two-pin one in addition to the six-pin connector (see pics). The wires on the six-pin seem to correspond although there's no ground that I can tell but there is a yellow and red wire that is cut. Should the ground be going through the same connector? Everything was really dirty. Former PO obviously didn't care about dirt.

Eventually with the first 3 pics, it'll be clear that what I have are a green and white, green and yellow and a green and black/really dark blue wire (all on the same row), and green only wire, plus a red and blue-stripped wire and cut yellow and red wire (all on the same row). These seem to correspond to the tail light configuration that Pngunme mentioned except there's no ground wire but there is that cut yellow and red one.

Here is where the wires are under the truck and the first split that I think Pngunme spoke of. There's the yellow and red wire again. Not sure where it goes or why it's cut.

This last one has nothing to do with the present problem but I saw one reason why my horn doesn't work (broken wire not attached). Two other wires going nowhere. I have a lot of those.

 

[bj40green]

Yellow/Red is the wire that goes to the FUEL sender. You have to figure out the "what happened & why".
Is your FUEL gauge working?

 

[Paraglider]

Yellow/Red is the wire that goes to the FUEL sender. You have to figure out the "what happened & why".
Is your FUEL gauge working?

Yes, the fuel gauge is working--one of only two (the temp gauge also)

Any thoughts on why the tail lights and license plate lights are not working (assuming the source is the same for the problem). I checked the connections on the rear ambulance door and everything seems good but no power is showing getting to those license plate lights, either.

 

[bj40green]

Yes, the fuel gauge is working--one of only two (the temp gauge also)

????? I'm confused. Funny because the Yellow/Red is cut off unless it's bypassed with another wire.

Follow the solid green wire back to the front or start at the beginning and check the TAIL fuse.
Use a voltage tester to see if you have voltage. Next test the light switch with your voltage tester.
See the FSM for details about wiring.

TB is power from fuse. TL (solid Green) is power to tail, license plate and side markers (running lights).
The TAIL fuse feeds the light switch 1st position and from there the side markers, tail lights and the license plate lights.
They are all on that same solid GREEN wire.

Rudi

 

[Solace in Solitude]

Edit: looks like Rudi answered while I was typing...

I don't know why your fuel sender would work, with the wire cut... Unless the PO has run another/separate wire directly to the fuel gauge... You'll need to pull the cluster to troubleshoot it... If you want... BE SURE YOU DISCONNECT THE BATTERY FIRST!!

My '78 tail/license/marker lights are via the solid green wire... I'm confused by @Coolerman 's comments/colors in post# 11... I'll leave it to Mark to help.

But, to my thinking, your green-only wire should be the wire that drives your tail/license/marker lights... Trace it from the firewall 6-pin to the lights and see what's been changed... From your first post, in this thread, it looks like your green gas been spliced to some other color at the tail lights...

Of course, it could be bad/no grounds...