FJ40 Wire Harness Reference - September 1976 (1 Viewer)

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woytovich

Science...
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I am in the process of doing some work on my 40 and I have the wiring harness out of the truck. I took this opportunity to photograph the harness in detail in the hopes of developing a useful wiring reference. (I have a MUCH larger version of this image also)

I believe this to be an unmolested September 1976 wire harness. (thanks AntFJ for the clarification)
I would like to identify each item on the harness, with additional details when necessary.

Here is the picture. As you'll see each item is numbered... I would like to create a table cross referencing the numbers with their application and additional details. On the image I would like to add a short description to each item (in addition to the number.). The table will get posted here and updated as needed.

Here is a large version of the below image (4.5mb):
https://forum.ih8mud.com/media/1976-harness.51836/full?d=1487176685

Here is a very large version:
WireHarness9_76_lrg.jpg


full


############################################################

NOTE: There is a 12/78 harness reference posted here:

FJ40 Wire Harness Reference - December 1978

############################################################
 
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i can tell you right now that is either a really really really early 1978 or a late 77 the 78 did not have the fasten seatbelt/brake lights that mount under the dash and a horn relay... what MONTH/YEAR exactly is this harness from??

(this is awesome btw)

Below should be a good start on what you've got
 
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1. Alternator
2. Alternator
3. Passenger Headlight
4. Passenger Horn
5. Ground
6. ?
7. Ground?
8. Pass Turn Signal
9. Pass Turn Signal
10. Oil Sender
11. Coil?
12. Coil?
13. Washer Motor
14. Fusible Link (goes to + Terminal on Battery)
15. Fan Blower
16. Rear Harness
17. Rear Harness
18. Distributor?
19. Distributor?
20. Starter
21. Starter?
22. Seatbelt Buzzer
23. ?
24. Radio Ground?
25. Radio?
26. Wiper Motor
27. Wipor Motor
28. Switch
29. Dash Light
30. Dash Light
31. Switch
32. Cig Lighter
33. Temp Sensor
34. Switch
35. Below Dash Light (for heater controls)
36. Rear Heater
37. Column
38. Column
39. Column
40. Annunciators
41. Brake Switch?
42. Parking Brake Switch?
43. Alt Gauge
44. Alt Gauge
45. Cluster
46. Parking Brake Switch?
47. Headlight Switch
48. Light Switch Light
49. ??
50. Computer
51. Fuse box
52. Ground
53. Emissions s***
54. ??
55. Idle Solenoid on Carb
56. Brake Pressure Switches on Master Cylinder
57. ??
58. Ground
59. ??
60. Drivers Horn
61. Drivers Headlight
62. Drivers Turn Signal
63. Drivers Turn Signal
64. ??
 
Thanks for the info!

Too many trucks taken apart, too many parts laying around: It was attached to a cowl with a VIN tag that says: SEP 1976
 
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IMHO there is no reason to use a '78 harness over the '76. They are so close to being the same I wouldn't bother. 'Specially given the hybrid collection of parts that makes up your truck. Were this a correct resto the answer would be different. I would use the harness in best condition and carry on. Yer doin' too much thinkin' and not enough doin' on some of this stuff ya know. :p

Not sure I would bother with "adapter harnesses" either. Just adds extra failure points to the electrical. Since it's not a resto there is no need to worry about maintaining the factory connectors. They are not weather tight and would even consider replacing some of them with newer GM WeatherPack or other weather resistent connectors. At least use heatshrinkable butt splices. But that would be the subject of a different thread...

:cheers:

Nick


This is off the topic some, and if this ever becomes part of the TECH section I'll edit this all out probably, but:




So... this brings up a different question for me... given that this cruiser is a "hybrid" - 79 2F motor, 76 wire harness, early bib and fender skirts with lights... - should I reconsider this harness?

What happened is I removed the rusty cowl (and harness) from the truck (IT is a SEP 1978 VIN/harness and I had it running with the 79 2F) and am replacing it with a 99% rust free cowl from this SEP 76 truck (the truck had an aluminum tub). The harness in the 76 is in better shape than the 78... but the 78 WAS working so there is not really problem there.

So, my question is: is there any significant reason to use the 78 harness instead of the 76? I am going to have to make adapters to get to the "early" stuff like the bib and skirt lights anyway (I prefer to not cut up the harness). And I still have the 78 cowl/harness so I can compare when connecting the 76 harness up to the 79 2F...

What do you think?

Mark
 
definitely man with what was said above - just modify this harness to suit your needs... i modified my 78' harness so that my early bib lights work as blinkers and parking lights - you can get all the connectors you want from Coolerman and it will still look clean and stock!

a sept 76 makes perfect sense that looks exactly like the oct 76 truck i took apart cool to know!
 
oh and 24 and 25 are the glove box plug

and now that i look at it again 13 is the horn relay and 59 is your wiper motor
 
Yer doin' too much thinkin' and not enough doin' on some of this stuff ya know.

I gotta do the thinkin'... I want to understand stuff, not just get it done. I've found that spending some time learning and thinking is worth the investment for me.

I do however understand what you are saying and I am TRYING to balance the thinkin' vs doin' better...
 
Great idea! Would you mind telling what software you used to stitch these pics together?

So it's verified that this is a 9/76 harness? If so the following matched my 76 harness. These were verified with meter and schematic.... I updated your spread sheet also

6 = RF Bypass capacitor
7 = To Ballast Resistor
10 = Coil +
11 = Ground
12 = To igniter
21 = Starter Bypass
23 = Buzzer Relay
41 = Key Switch
42 = Park Brake Switch
43 = Amp Gauge
44 = Amp Gauge
46 = Turn Signal Flasher
48 = Head Light Switch Bulb Socket
49 = Interior light
53 = Regulator
54 = Washer Pump
64 = Radio B+
 
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If anyone is interested I can get a lot of the common latching connectors for the 73-83 harnesses.

Some that are NOT available include the weird dizzy connectors, regulator connector, fuse block connector (though I may have a source for the terminals) Emissions computer connector, hazard switch connector and tail light connectors.

Just email me what you need and I'll tell you if I can get them....
 
Subscribed...I'm a couple weeks away from tackling this issue. Thanks for the info.
 
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Any idea what 57 is... thanks so much for posting this

I got 2 76's and one has hacked up wiring..
 
I will see if I can figure 57 out...

I am SO glad this is proving helpful... :clap:

I have gotten so much from the folks on mud it's nice to be able to give back in some tiny way.
 
57=washer motor?
 
This is a great resource...Thanks
 

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