1978 turn/hazard wiring schematic

[Chevypower]

OK, so i got a set of 78 switches from another MUD user, and am now ready to start.
Long story short, I am so confused I can't see strait, and I haven't even started. My plan is to write down every wire # (painless wire #) that goes to each switch wire, then install and hook up the wires. I'm going to start with the steering column and hazard switch in this thread, then do another thread about the others.
I'm going to be asking questions and documenting every wire # and every switch wire color and when I'm done I will do a separate post and run down every connection I did so future members can just follow along. This is something I can't seem to find on this site, so hopefully I'll be the first, but not last to do this.

So this is where i'm at for the night. 1978 steering column wires and how they ring out. (column is not hooked up)

2 position plug:
WB ground
GR (Horn I think)

6 position plug:
GB (Green/Black)
GW (Green/White)
GY (Green/Yellow)
RG (Red/Green)
RW (Red/White)
RY (Red/Yellow)
With the right turn signal on I get continuity with GY to GW adn RY to RW
With the left turn signal on I get GW to GB and RY to RW
With the lever in the center position, I get RY to RW (also in right AND left turn position)

Can anyone help with what wire color does what or how to test to see. I have the wiring schematic, but it doesn't show the 2 or 6 position plugs or the pin out of the column like it does for the switches.

I do have a sketch of the electrical connections from another thread that I now can't find, showing the the connections in the turn positions, but the wire colors are not labeled, and I don't know how to read it. I will do more searching and try and find it again..

 

[Chevypower]

After typing this, I looked at it again.

GY looks like it goes to Right Hand signal, and the GY on the Hazard switch.
GB looks like it goes to Left Hand signal, and the GB on the Hazard switch.

But, isn't there a Front and Rear signal wire for both Right and Left, for a total of 4 wires, not the above 2.

 

[subzali]

There is a wiring diagram in the tech links, I posted a link to it in your other thread:
https://forum.ih8mud.com/40-55-series-tech/549583-what-year-wiring.html

Doesn't that tell you all you need to know? The color codes are pretty similar for '76-'78 stuff, small differences here and there.

 

[Chevypower]

No it doesn't because the schematic doesn't show the blinker wires. All it shows is the GB and GY wires.

 

[miker]

The column has a couple other switches too like horn and hi/lo beams. I looked at the schemetic, here's what I came up with, but yours may be different:

GL (green/light blue stripe) - from turn/haz flasher - this is the power feed to the turn signal switch
GY (green/yellow stripe) - to RH turn bulbs, FT and RR
GB (green/black stripe) - to LH turn bulbs FT and RR
GR (green/red stripe) - to horn (this wire is grounded at the column when horn button is pressed)
RG (red/green stripe) - headlamp low beam
RY (red/yellow stripe) - headlamp high beam

Suggestion, try to make sure you are using the correct Toyota abbreviation for the wire colors or better yet spell them out otherwise what you document for others to follow can be confusing.

 

[Chevypower]

miker,
I'll have to look again at the colors when I get home, but I'm sure what I put down is the correct Toyota colors I have. But yes, I will spell them out as well. After I look at it, I'll try and dig into the hazard switch and will post up what I find, witch will probably be more questions.
How about the 2 position plug, do you think the White/Black is ground and the Green/Red is ????????

"Yuba City Girls Make The World Go Round"

 

[miker]

WB (white with black stripe), I think, is only used for ground so that would be a good guess.
The GR (green/red stripe) could be the horn.

Just a bit of caution about the wire colors I listed above, those colors were from the schematic showing the color of the wire in the main loom. It sounds like you don't have the OEM loom and are using a Painless harness. One thing I've noticed working on a few cruisers is that the color on the OEM schematic is generally showing you what color wire is being used in the OEM main wire loom only and when that wire runs to a connector, like on the steering column, the mating wire for that terminal could be a different color.

I would take the plastic covers off the column, and remove the steering wheel, so it gives you a better idea how the wires are routed and therefore where the wires are going, like ignition switch, turn signal switch, etc. With that said, with enough patience and a DMV/Ohm meter, you should be able to figure out each wire without taking it apart.

BTW, I believe that the ignition switch is a separate connector and has 4 wires.

I'm sure most, if not all this info is here on mud already, it may be just a matter of finding it.

 

[Chevypower]

So I took the plastic cover off and I have written out the wire colors in my first post. The 2 position plug, the second wire (Green/Red) goes to a metal "finger" that makes contact with the back of the steering wheel.

The Painless wire schematic calls out the following wires to be hooked up to the column:

Horn
LF Turn Signal
RF Turn Signal
Hazard Flasher
Turn Flasher
LR Turn Signal
RR Turn Signal
Stop Lamp Switch

 

[Fast Eddy]

One thing I've noticed working on a few cruisers is that the color on the OEM schematic is generally showing you what color wire is being used in the OEM main wire loom only and when that wire runs to a connector, like on the steering column, the mating wire for that terminal could be a different color.

That is not my experience with my '76 and '78. Even the pigtails on the switches use the main harness standard colors. I haven't really done that much work on the wiring however. They're both in pretty good shape for 35 years old.

 

[Pin_Head]

Painless wire kits don't work with the 75 and up Toyota turn and brake lights, so you have to wire these up yourself if you want to keep the stock column and switches. They are designed to work and be plug compatible with GM columns, which are similar wiring to 74 and earlier FJ40s.

The main difference is that 75 and later cruisers have separate rear turn and brake bulbs. You need to run a new wire from the brake switch to both rear brake bulbs. The turn signals use the same wire output of the turn signal switch, so you combine the front and rear wires for each side.

 

[miker]

2 position plug:
With the right turn signal on I get continuity with GY to GW adn RY to RW
With the left turn signal on I get GW to GB and RY to RW
With the lever in the center position, I get RY to RW (also in right AND left turn position)

Can anyone help with what wire color does what or how to test to see

you could also check continuity of the R/G, R/W, R/Y with the turn signal lever pushed forward for high beams, and then pulled back (spring loaded) for passing/signal lights (high and low on together.

The 2 position plug, the second wire (Green/Red) goes to a metal "finger" that makes contact with the back of the steering wheel.

this is the horn as you suspected.

 

[Chevypower]

Painless wire kits don't work with the 75 and up Toyota turn and brake lights, so you have to wire these up yourself if you want to keep the stock column and switches. They are designed to work and be plug compatible with GM columns, which are similar wiring to 74 and earlier FJ40s.

The main difference is that 75 and later cruisers have separate rear turn and brake bulbs. You need to run a new wire from the brake switch to both rear brake bulbs. The turn signals use the same wire output of the turn signal switch, so you combine the front and rear wires for each side.

So what your saying is that I will have to create, with new wires that i have to now go and buy, the entire turn, hazard, low and bright, and brake system?????

 

[Chevypower]

OK, so all that is really needed to be "re-created" is the following:

1) the GW wire from the hazard switch to the flasher, from flasher to the GL wire on turn signal (on steering column, it's actually GW on my column but GL on schematics).
2) the GY wire from hazards to (high beam) GB wire on turn signal
3) the GB wire from Hazard to (low beam) GY wire on turn signal
4) the GL wire from hazard to GL wire on turn signal (same connection as end of #1 above)

This takes care of 3 of the 6 wires on my turn signal. the other 3 are as follows:
1) RY wire to harness #708 High beam
2) RW wire to harness #707 headlight switch
3) RG wire to #709 to low beam

 

[Chevypower]

http://www.yankeetoys.org/documents/...am_78_fj40.pdf

This 1977 wire schematic that Subzali refers to in my different post, shows one Red wire from the fuse panel to the light switch and Head light dimmer switch (in the 6 pin connector on the steering column). This red wire would be the 7th wire going into that plug if I am looking at this correctly. I don't think I am, so can someone help me out with this one Red wire.

 

[Fast Eddy]

Your link doesn't work, and it says '78 right in the name. Here's a link to a '78 diagram:

http://www.ih8mud.com/tech/pdf/fj40_wiring_diagram.pdf