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Hello everyone, I need help figuring out the wiring mess under the hood
I was working on my electric fan wiring after I found a fuse melted under the dash, and found a bunch of wires cut / spliced in etc.... Melted electric fan fuse
I am cleaning it all up and putting a separate relay / circuit for the electric fan with it's on temp sensor.. .. but in the process I found that I have a green wire that goes to the high pressure A/C line sensor/valve that has a spliced in wire appears to be the same cable color / size see pic bellow it was going to the driver's side of the engine together with the choke wire but not connected to anything
Spliced in cable going to the high pressure A/C line sensor/valve Cable that was going to the driver's side under the carb linkage but was not connected to anything High pressure a/c line sensor / valve
One more thing the A/C clutch pigtail was damaged by rubbing on the clutch pulley I bought I new one to replace my a/c does not work it has a leak but I am going to fix it eventually, the plug fits both ways what side is the ground that goes to the a/c bracket? while working on the electric fan wire I found a second damaged a/c plug tucked in the fender where the second wire was going to but ending there... where does the second wire for the a/c plug connects to?
One last question where does the original electric choke cable connects to and what color is it?
Thanks for your time and I really appreciate the help.
Assume 79? If manual, no idle solenoid..it may extend on yours from compressor power.
this thread has 79 color diagrams from original manual. You may also have factory electric auxiliary fan. Some pics if helpful.ignore auxiliary fan switch i added. https://www.corvetteforum.com/forums...-in-color.html
Note, this thread is my ‘have factory electric fan comes on with ac’ and has lots pics https://www.corvetteforum.com/forums...-option-3.html
Last edited by interpon; Mar 19, 2025 at 09:01 AM.
Here is the 79 drawing...
You will see the symbol S66 on the drawing S=Splice the 66 is the number of the splice joint.
The connector not connected anything was meant to connect to the Idle Stop Solenoid on the carburetor, if you have a Manual transmission then there was NO ISS.
The Lt.Grn wires are HOT anytime the A/C selector switch is to NORM or MAX positions.
After that the wire colors change after the LPCS (Low Pressure Cutoff Switch) and again after the TS (Thermostatic Switch)...
I'm not 100% sure about the choke wiring, I thought the 79 still had the Hot Air Choke system...
Last edited by bmotojoe; Mar 19, 2025 at 08:31 AM.
Assume 79? If manual, no idle solenoid..it may extend on yours from compressor power.
this thread has 79 color diagrams from original manual. You may also have factory electric auxiliary fan. Some pics if helpful.ignore auxiliary fan switch i added. https://www.corvetteforum.com/forums...-in-color.html
Note, this thread is my ‘have factory electric fan comes on with ac’ and has lots pics https://www.corvetteforum.com/forums...-option-3.html
Thank you interpon...
Yes it is a 79 L82 automatic, those diagrams helped a lot thanks... I think I am missing the Idle Speed Selenoid... Should I order one for when I get my a/c fixed?
Here is the 79 drawing...
You will see the symbol S66 on the drawing S=Splice the 66 is the number of the splice joint.
The connector not connected anything was meant to connect to the Idle Stop Solenoid on the carburetor, if you have a Manual transmission then there was NO ISS.
The Lt.Grn wires are HOT anytime the A/C selector switch is to NORM or MAX positions.
After that the wire colors change after the LPCS (Low Pressure Cutoff Switch) and again after the TS (Thermostatic Switch)...
I'm not 100% sure about the choke wiring, I thought the 79 still had the Hot Air Choke system...
Thanks bmotojoe,
Thank you for your time, I am glad I did not cut it off, do you know if I need to add ISS since my car is auto? I wish it was manual
These diagrams will help me a lot this weekend when I got back to work on the car...
Thank you for your time, I am glad I did not cut it off, do you know if I need to add ISS since my car is auto? I wish it was manual
These diagrams will help me a lot this weekend when I got back to work on the car...
If you have a little slack in those Lt.Grn wires cut them back a little to expose some fresh wire, then insulate the new splice joint area.
Have a new ISS on hand when you are ready to charge the A/C system. Being you have a AT when the compressor kicks on and you are in drive the RPMs will drop several hundred because of the extra load.
I will do that I have some slack, and thank you for the info on the ISS I just ordered one trying to get all fixed to have a/c this summer otherwise I can't use the car here in South Florida...
Have a great night and thanks again for your time and sharing you knowledge!!!!
Thank you for posting this pic of this wiring diagram. It helped solve a blower fan switch issue I was having with no power to the switch (yellow wire was dead). Ends up it was a bent connector at the a/c selector switch (the yellow one of course). Bent it back, reconnected and bam, power to the switch.
A/C Clutch wiring
