A/c woes
Thread Starter
4th Gear
Joined: Mar 2022
Posts: 5
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From: Arizona
A/c woes
I purchased this 92 with a burnt engine harness and it is my first vette, so I didn’t know that the engine harnesses are different between manual and auto climate control cars. And of course I got the harness for a manual climate control version. Can I convert mine to manual or? I have changed the blower speed control resistor to what it’s supposed to be for the manual but I’m still getting nothing at all (other than the backlight) on the display.. tia for any help and yes, I’ve checked all fuses.
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From: Compound in the Grove, Ga.
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St. Jude Donor '16
Good to see ya over here, Hope someone has an answer for ya.
Team Owner
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For your '92 there there would only be one correct harness. Mention the RPO on your SPID label on the console lid. An MD8(automatic) car would have 2 different, 1 for AC C60 and another for an ATC C68, an M6 (manual transmission) would have the same 2 different options. There's actually 4 (total). On the used that you bought if there's wrap of tape around the harness with information the one you bought can be identified, the tape is generally around the vicinity of C100 connector. If you bought from a salvage yard they often include a VIN on the invoice. If there's a VIN on the invoice or if you can contact the seller and get a VIN it can be identified.
Converting a C60 to C68 or a C68 to C60 is a mammoth undertaking. I know a fellow who started, spent several days and finally actually tossed what he bought and bought another. His was a very expensive experience.
Need to know much more regarding your cars options and if you can get more information regarding the car it came from it would be very helpful.
A very experience C4 person if the harness were laid out on a table or floor could ID it as to being from an MD8 (automatic) or an MN6 M6 (manual transmission) car.
Do you have the FSM?
Converting a C60 to C68 or a C68 to C60 is a mammoth undertaking. I know a fellow who started, spent several days and finally actually tossed what he bought and bought another. His was a very expensive experience.
Need to know much more regarding your cars options and if you can get more information regarding the car it came from it would be very helpful.
A very experience C4 person if the harness were laid out on a table or floor could ID it as to being from an MD8 (automatic) or an MN6 M6 (manual transmission) car.
Do you have the FSM?
Last edited by WVZR-1; Mar 24, 2022 at 09:36 PM.
Race Director
Joined: Feb 2002
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From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
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St. Jude Donor '16
Dave,
Torch'd is a friend we have talked. he has a 92 M6 with auto air (68), the harness he replaced the burnt one with is for a (C60). I was hoping you would post and possibly know a work around or can he change to a C60 head unit? I'm not sure how it is integrated in the dash wiring.
Torch'd is a friend we have talked. he has a 92 M6 with auto air (68), the harness he replaced the burnt one with is for a (C60). I was hoping you would post and possibly know a work around or can he change to a C60 head unit? I'm not sure how it is integrated in the dash wiring.
Team Owner
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A correct harness for the car would be a GM# 12125012 - M6 w/C68 It is a '92 only harness.
He's actually in Arizona?
Last edited by WVZR-1; Mar 24, 2022 at 09:53 PM.
Race Director
Joined: Feb 2002
Posts: 11,610
Likes: 1,053
From: Compound in the Grove, Ga.
2026 Corvette of the Year Finalist - Unmodified
2025 C4 of the Year Winner - Unmodified
2024 C4 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
2019 C4 of Year Finalist (performance mods)
2018 C4 of Year Finalist
2015 C4 of the Year Finalist
St. Jude Donor '16
Thread Starter
4th Gear
Joined: Mar 2022
Posts: 5
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From: Arizona
So it is an M6 harness just for a C60 vs the C68. Depending on how expensive the harness he bought was I believe it would be best to buy a 'known' correct harness. If he's not modified what he's bought he could recover maybe most or some of the $$$$.
A correct harness for the car would be a GM# 12125012 - M6 w/C68 It is a '92 only harness.
A correct harness for the car would be a GM# 12125012 - M6 w/C68 It is a '92 only harness.
Team Owner
Joined: Sep 2003
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Thread Starter
4th Gear
Joined: Mar 2022
Posts: 5
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From: Arizona
Nope, no numbers. It’s the right harness for an M6 C60 car. 🤷🏻♂️ And I did buy it new. The main goal at the time was to get it running 😁…. Figuring that there was a work around for the A/c issue 🤷🏻♂️