69 wire harness replacement
Thread Starter
Pro
Joined: Sep 2002
Posts: 541
Likes: 5
From: Epping NH
69 wire harness replacement
I have had a battery die several times in the past week and when I brought the car to my mechanic for eval, he tested the voltage at the alternator and found that it was putting out 32 volts! We ran a separate ground from the battery to the alternator and it read about 12 volts. So, it seems as though I may have a short somewhere. I have an inductance meter that I plan to test the system with (plug a balast resister in the fuse box and run the meter along the associated wires to look for shorts), but I am skeptical about finding the problem that way. I have a new power cable running from the battery to the starter, but other than that I can not vouch for any of the wiring in the car.
I know that replacing the wiring harness is not a job for the faint of heart, but I have had the car completely apart before (as close to a frame off as you can get without taking the car off the frame). Assuming that I do not find the problem with the meter, can anyone recommend a source of a replacement wiring harness? I recall reading that there are exact replacement harnesses available, but don't remember who makes them or where to purchase. Thanks.
Mark
I know that replacing the wiring harness is not a job for the faint of heart, but I have had the car completely apart before (as close to a frame off as you can get without taking the car off the frame). Assuming that I do not find the problem with the meter, can anyone recommend a source of a replacement wiring harness? I recall reading that there are exact replacement harnesses available, but don't remember who makes them or where to purchase. Thanks.
Mark
Race Director
Joined: Apr 2003
Posts: 19,347
Likes: 654
From: Tampa, Florida
Lectric Limited harness available from one of the vendors.
Replacing the 'ignition' (engine) harness and 'front' (lighting) harnesses is a piece of cake. The ignition (engine) harness can swapped out in ~2 hours.
Pick up one of the 'Laminated & colored' schematics to help you along!!!
Replacing the 'ignition' (engine) harness and 'front' (lighting) harnesses is a piece of cake. The ignition (engine) harness can swapped out in ~2 hours.
Pick up one of the 'Laminated & colored' schematics to help you along!!!
Le Mans Master
Joined: Sep 2000
Posts: 9,078
Likes: 7
From: DFW TX
Cruise-In VII Veteran
St. Jude Donor '07
There are two harness in the engine bay. It splits at the connector. The alt harness includes the front fiber optics also. I replaced the engine wiper side in about two hours the other night. No big deal at all. You are probably thinking of the dash harness, it can be a major pain in the ash. I choose the Lecticlimited and it is a perfect exact reproduction.
One tip for you. Buy the diagram when you order the harness.
One tip for you. Buy the diagram when you order the harness.
Thread Starter
Pro
Joined: Sep 2002
Posts: 541
Likes: 5
From: Epping NH
Thanks for the replies
I just checked with Lectric Limited and they indicated that there are 4 harnesses in my car. If I don't find the problem, where to start?? I'd guess the engine and headlights since they are right up front, and the cheapest! Thanks for all of your help!
Mark
Mark
Burning Brakes
Joined: Jun 2004
Posts: 872
Likes: 3
From: Cortlandt Manor New York
I replace my rear harness over the winter and there were no problems. It was not that difficult and if you take your time and be careful it is done in 2-3 hours after your carpet and trim is removed.
Lectric Limited has the best wiring harnesses with all the correct connectors and Dr. Rebuild has a great laminated wiring diagram that is well worth the $ ($12 I believe).
Good Luck
Lectric Limited has the best wiring harnesses with all the correct connectors and Dr. Rebuild has a great laminated wiring diagram that is well worth the $ ($12 I believe).
Good Luck
Burning Brakes
Joined: Mar 1999
Posts: 1,047
Likes: 3
From: CA
Lectriclimited is way to go but purchase from The Last Detail. I remember it was cheaper going through them when I priced these out. Even though you are purchasing through TLD, they are shipped directly from lectriclimited.
Not sure how you can go from 32 volts to 12 volts, but why not just remove the alternator and bring into your favorite parts store for testing. Eliminate the easy to replace parts first before replacing the harnesses. And if I remember correctly your car has a separate voltage regulator (but I could be wrong)...if you do you will need to test that as well.
When I eventually replaced the harnesses on my car I just did them all and got it out of the way. The wires were getting old and brittle and I didn't want to take any changes.
Good luck.
Not sure how you can go from 32 volts to 12 volts, but why not just remove the alternator and bring into your favorite parts store for testing. Eliminate the easy to replace parts first before replacing the harnesses. And if I remember correctly your car has a separate voltage regulator (but I could be wrong)...if you do you will need to test that as well.
When I eventually replaced the harnesses on my car I just did them all and got it out of the way. The wires were getting old and brittle and I didn't want to take any changes.
Good luck.
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Burning Brakes
Joined: Feb 2005
Posts: 1,235
Likes: 0
From: Mesa AZ
get the alt., voltage regulator , and battery tested first. why not just go through the whole harness and try to find the problem? you said you've had the whole car apart before so you obviously have the skills needed to fix it.
Race Director
Joined: Apr 2003
Posts: 19,347
Likes: 654
From: Tampa, Florida
1. Trunk/rear light....
2. Dash
3. Engine/ignition....
4. Front/alternator/headlight
Buy 3 & 4 at the same time. as others have noted they are very easy to install.
This is a pic of the block on the lower drives side firewall. The center bolt doesnt come out!! Loosen the bolt, pull the block out a little, loosen the bolt some more and pull out on the block some more. As you can see one of the harness slides off to the side..
The other harness is integral to the block:
The 'easiness' of the install depends solely on these to connections. Make them first because they will 'center' the ignition harness. If your harness is too much to the left or right niether will connect!!! Make thse 2 first!!
Make sure the harness is tucked in tight to the firewall!! You dont want it touching the exhaust manifold!!
Thread Starter
Pro
Joined: Sep 2002
Posts: 541
Likes: 5
From: Epping NH
Wow
Thanks for the heads up! I will start playing with the inductance meter today to look for an easy fix..... yeah right. If I don't have much luck I will probably order the two harnesses and dig into it next week. Since I have replaced all vacuum hoses, I sorta have a sense as to how this is gonna go.
Mark
Mark
Drifting
Joined: Jul 2005
Posts: 1,562
Likes: 2
From: Spring Texas
. You will still have 32 volts until you get a good regulator in that alternator.
