1978 FJ40 - Wiring Help (2 Viewers)

[Not A CJ]

I have been fighting the wiring gremlins of the PO. I have several things sorted out but I am now tackling my reverse lights as they are not working. Your help may explain why the windshield washer is not working or why when I hit the brakes the turn signal indicators light up on the gauge cluster.

I have learned with this rig that if there is electrical tape anywhere just remove it and see what you find.

As a result I have the following questions based on the pictures below:
Picture #1 - any ideas what should be connected here?
Picture #2 - is this part of the reverse lights? (found this one behind the dash)
Picture #3 - can anyone identify the four wires in the picture
Diagram - is this one f the better references? (yes, I blew it up poster sized)

Any help would be awesome

 

[Not A CJ]

Found an additional picture that show what the thicker black cable looks like. I have been searching around the forum and it looks like this wire may connect to the gearshift? That harness used to be green before it got covered with gunk from a leaking rear main seal

 

[Bear]

Like the wiring diagram !

 

[Solace in Solitude]

Great wiring diagram!!

If it's a '78 diagram, use it

I'm on vacation and on an iPhone and colorblind... I can't make out a lot of what your pictures show.

1. Lite blue/red strip is "LR"... LR is backup lights... LR connects to the backup light switch on the tranny.

2. Can't see the colors... can't help

3. Can't read your questions... or see your wire colors... colorblind... I know they are there, but can't make them out.

So...

click this -->
Page 062 Land Cruiser 4 speed Transmission

Click the "backup switch location"

Click the image for your year

See the wired backup switch

Good luck!!

Maybe Rudi (@bj40green) or Mark (@Coolerman ) can see your pics more clearly.

 

[Rusty 72]

I have a 78 transmission and it has the reverse switch and another switch on top of shifter tower. Read where it's supposed to work when transmission is in 4th. It's a single wire switch.

 

[Catfish28]

Here is what I used to redo my 78.
FJ40 Wire Harness Reference - December 1978

Believe wire in pic 1 is unused on a 78
Pic 3 wires. Ones on the left go to reverse switch on top of tranny.

 

[Not A CJ]

Great wiring diagram!!

If it's a '78 diagram, use it

I'm on vacation and on an iPhone and colorblind... I can't make out a lot of what your pictures show.

1. Lite blue/red strip is "LR"... LR is backup lights... LR connects to the backup light switch on the tranny.

2. Can't see the colors... can't help

3. Can't read your questions... or see your wire colors... colorblind... I know they are there, but can't make them out.

So...

click this -->
Page 062 Land Cruiser 4 speed Transmission

Click the "backup switch location"

Click the image for your year

See the wired backup switch

Good luck!!

Maybe Rudi (@bj40green) or Mark (@Coolerman ) can see your pics more clearly.

Thank you for the help.

Thanks for the link. I will help you out with the colors as well
pic 1. is LR and connected the the reverse switch. I am not sure which of the wires from pic #3 goes to the switch as well
pic 2. WB and LR
pic 3. #1 LR #2 Light blue #3 Thick Black #4 light blue

 

[Not A CJ]

I have a 78 transmission and it has the reverse switch and another switch on top of shifter tower. Read where it's supposed to work when transmission is in 4th. It's a single wire switch.

DO you know what the one is for on the shift tower?

 

[Not A CJ]

Here is what I used to redo my 78.
FJ40 Wire Harness Reference - December 1978

Believe wire in pic 1 is unused on a 78
Pic 3 wires. Ones on the left go to reverse switch on top of tranny.

Thank you. I am going to print out a large color copy of that harness.

Pic 1 - Glad to hear that the PO did not leave anything out on that one
Pic 3 - At there is a LR wire already connected. I am not sure what other wire to connect.

 

[Solace in Solitude]

DO you know what the one is for on the shift tower?

High Gear Indicator - for the Emissions Computer.

Read thru this link and check against the appropriate wiring schematic.

Wire hanging on 78 FJ40 drive shaft...

 

[Rusty 72]

DO you know what the one is for on the shift tower?

It memory is correct it sends siginal to computer and says it's in 4th gear. It one year only. I really did not look any further.

 

[Solace in Solitude]

High Gear Indicator - for the Emissions Computer.

Read thru this link and check against the appropriate wiring schematic.

Wire hanging on 78 FJ40 drive shaft...

On this 1978 Wiring Diagram, it looks like it's called "transmission position switch" (on my iPhone), right of the "backup switch".

LR (Lite Blue, Red Stripe) to Backup Switch

RL (Red, Lite Blue Stripe) from backup switch to each backup light

G (green) to Transmission Position Switch

 

[mtn2roady]

Posting for others. I did an H55F swap in my 40 a couple years ago but never got around to the reverse lights. I got the female cannon plug for tranny and associated OEM bullet connectors from Toyota Matt (thanks Matt). 12V for left and right side of reverse lights off the harness are both located on passenger side chassis roughly a foot behind the fuel tank. On a 78 FJ 40, LR is +12V and light blue is ground. Join the left and right + and - for each side together. Attach female bullet connectors, it doesn’t matter which one goes to which on the switch. Hope this helps folks get their reverse lights going on the 40 with an H55F.

 

[mtn2roady]

Bam!