Voltage Drop @ AC compressor connection
Thread Starter
Safety Car
Joined: Sep 2011
Posts: 4,117
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From: Madeira Beach, FL
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Voltage Drop @ AC compressor connection
Voltage Drop Question:
Hello Forum.
I am restoring my AC in my 68 BB and coming into the home stretch. I checked my battery voltage at the terminals and I have 12.4 volts. At the pig tail for the compressor connection of the stock wiring I have 10.6 volts.
The AC position is on in the console, fan set on Hi, and temp set to cold.
I ran an auxillary black ground wire from the grounding point on the compressor bracket to the ground point on the fan relay as the new compressor housing in aluminum.
Is this about right with the car not running to have 1.8 volt drop?
PS: I pulled a deep vac and have a leak some where? So now I will add some R134 for leak test purposes and get my sniffer going. I can then locate the leak, correct and pull a vac and recharge with R-12.
Any and all comments welcome.
Thanks,
Marshal
Hello Forum.
I am restoring my AC in my 68 BB and coming into the home stretch. I checked my battery voltage at the terminals and I have 12.4 volts. At the pig tail for the compressor connection of the stock wiring I have 10.6 volts.
The AC position is on in the console, fan set on Hi, and temp set to cold.
I ran an auxillary black ground wire from the grounding point on the compressor bracket to the ground point on the fan relay as the new compressor housing in aluminum.
Is this about right with the car not running to have 1.8 volt drop?
PS: I pulled a deep vac and have a leak some where? So now I will add some R134 for leak test purposes and get my sniffer going. I can then locate the leak, correct and pull a vac and recharge with R-12.
Any and all comments welcome.
Thanks,
Marshal
Pro
Joined: Nov 2016
Posts: 729
Likes: 118
From: Kelowna British Columbia
If the car is not running and you have the key on there will be resistance and voltage drop at compressor. Now if the key is off you should have 12.6 at pigtail unless someone has hot wired it where it is live all the time
Thread Starter
Safety Car
Joined: Sep 2011
Posts: 4,117
Likes: 1,230
From: Madeira Beach, FL
2024 C8 of the Year Finalist - Unmodified
2024 C2 of the Year Finalist - Unmodified
2023 C2 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
Have power or have not with key off? I didnt think the a.c. connector was continuously hot?
Thanks,
Marshal
Thanks,
Marshal
Last edited by marshal135; Oct 18, 2020 at 02:25 PM.
