71 Automatic wiring diagram needed
Thread Starter
Burning Brakes
Joined: Oct 2004
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71 Automatic wiring diagram needed
Alright guys and gals, I'm currently in the process of installing my engine, dash, and forward lamp harnesses for a 71 automatic small block. I'm having a good bit of problems with the diagrams I am following. I bought the following wiring diagrams: http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW and a 71 Chevrolet Chassis service manual (shop manual) - I don't have the Factory Assembly manual. The thing is... the wire colors on the harness I have match up perfectly with my old harness's but on the wiring diagrams, the colors on the main plugs don't even match 
. Can anyone please help me with this?!
Thanks,
Michael
. Can anyone please help me with this?!Thanks,
Michael
Last edited by majic1984; Dec 12, 2004 at 05:09 PM.
Thread Starter
Burning Brakes
Joined: Oct 2004
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Originally Posted by Jack71
I would buy the diagram from lectriclimited.com There's is pretty accurate (although there are always minor deviations)
Le Mans Master
Joined: Sep 2000
Posts: 5,635
Likes: 4
From: Orlando Floriduh
Originally Posted by majic1984
Minor deviations such as wrong colors on the main plugs? (ones that screw onto the back of the dash harness)? Because the ones I have right now don't even match the damn wire colors comming from the plugs at the start of the harness.
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
Not sure what you mean that the colors on the plugs don't match. GM is very good about keeping wire colors constant through the years. The position on the fuse panel/firewall bulkhead passthrough of the wires varies year-to-year but the wire colors remain constant. Are you sure your new harness is for the correct year?
Last edited by markdtn; Dec 13, 2004 at 08:00 AM.
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Thread Starter
Burning Brakes
Joined: Oct 2004
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Originally Posted by markdtn
Not sure what you mean that the colors on the plugs don't match. GM is very good about keeping wire colors constant through the years. The position on the fuse panel/firewall bulkhead passthrough of the wires varies year-to-year but the wire colors remain constant. Are you sure your new harness is for the correct year?
- Michael
Last edited by majic1984; Dec 13, 2004 at 12:00 PM.
Le Mans Master
Joined: Aug 2003
Posts: 7,720
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From: Chattanooga TN
That's what I was referring to. If the wire positions on the fuse box don't match the one you are taking out then the harness is not the same. There are 2 possibilities for this:
1) They sent the wrong year harness to you. Honest mistake.
2) You have the wrong year harness in the car now. 69-71 (and 72 if you don't mind not having fiberoptics, and 73-75 if you don't have a wiper door either) harnesses will interchange if you use the whole thing from the donor car. I have a 72 harness in my 69. I added the fiberoptics.
Bottom line: If your pin positions don't match you need to find out why. Do the pin positions on the new harness match the factory wiring diagram? I think your original post says no. Does your new harness match the old location-for-location? If the pins on the new harness match the wiring diagram, you have the wrong harness in the car now. If the pin locations don't match the diagram, then the new harness was packed wrong and is for a different year.
1) They sent the wrong year harness to you. Honest mistake.
2) You have the wrong year harness in the car now. 69-71 (and 72 if you don't mind not having fiberoptics, and 73-75 if you don't have a wiper door either) harnesses will interchange if you use the whole thing from the donor car. I have a 72 harness in my 69. I added the fiberoptics.
Bottom line: If your pin positions don't match you need to find out why. Do the pin positions on the new harness match the factory wiring diagram? I think your original post says no. Does your new harness match the old location-for-location? If the pins on the new harness match the wiring diagram, you have the wrong harness in the car now. If the pin locations don't match the diagram, then the new harness was packed wrong and is for a different year.
Thread Starter
Burning Brakes
Joined: Oct 2004
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Originally Posted by markdtn
If the wire positions on the fuse box don't match the one you are taking out then the harness is not the same.
Originally Posted by markdtn
Do the pin positions on the new harness match the factory wiring diagram?
Originally Posted by markdtn
Does your new harness match the old location-for-location?
Originally Posted by markdtn
If the pin locations don't match the diagram, then the new harness was packed wrong and is for a different year.
- Michael
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
You can read the pin locations from the shop manual wiring diagram. That's all you really need.
The "C-shaped" part of the harness was used on many GM cars from early 60s into the 80s so it is hardly unique. So it will physically interchange even if all the wires are in the wrong locations. The only difference in a 68, 69, 70, and a 71 Corvette engine harness is pin locations and horn buzzer wiring (same goes for 72 except fiberoptics). If your wires are not in the same location on the new harness as the old, they are from different years or wired wrong.
edit-68 is different due to alternator wiring.
The "C-shaped" part of the harness was used on many GM cars from early 60s into the 80s so it is hardly unique. So it will physically interchange even if all the wires are in the wrong locations. The only difference in a 68, 69, 70, and a 71 Corvette engine harness is pin locations and horn buzzer wiring (same goes for 72 except fiberoptics). If your wires are not in the same location on the new harness as the old, they are from different years or wired wrong.
edit-68 is different due to alternator wiring.
Thread Starter
Burning Brakes
Joined: Oct 2004
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Called M&H and verifed the harness. Nothing is wrong with it, it's the correct year. Apparently some of the wiring diagrams for these cars were made 1 year in advance of actual production of the harnesses, therefore creating major differences. I have a copy of the factory assembly manual diagrams now (they look different from both of the ones I've got). I will compare those to my harness tonight and tell you guys whats going on. Thanks for all your help, wish me luck. *crosses fingers*
-Michael
-Michael
Le Mans Master
Joined: Sep 2000
Posts: 5,635
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From: Orlando Floriduh
I looked through what is left of my 71 GM manual.. There are a few pages missing but there doesn't appear to be a full schematic. Just for the A/C and some other car line accesories. I do however have a 4 page wiring diagram in a haynes manual that seems to be a copy of a GM manual. If you want that I will scan it and send it to you Via E-mail. let me know
Thread Starter
Burning Brakes
Joined: Oct 2004
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Hrm, seems the Factory Assembly Manual's diagram matches my harness (colors and all) perfectly. I'm not sure if Larry B. has one of these diagrams, but the one the M&H guys faxed me is very poor resolution although I can barely make out what the colors say. I was wondering if anyone could make a hi-res scan of it for me please.
Thanks,
Michael
Thanks,
Michael
Thread Starter
Burning Brakes
Joined: Oct 2004
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Here's the wiring diagram that I said was correct (Out of the factory assembly manual). If anyone has a clearer one like it for a 71, could you please send it to me?
http://members.***.net/gdeb/scan0003.jpg
Thanks,
Michael
http://members.***.net/gdeb/scan0003.jpg
Thanks,
Michael
