Ac compressor will not come on?

1996 CHEVROLET TAHOE
V8 • 4WD • AUTOMATIC
Avatar
STACIE5606
  • MEMBER
  • 1 POST
ac compressor will not come on unless we jump it from the compressor to the battery. We have replaced cycle switches, control unit in the dash, all lines, accumulator, condenser and orifice tube and relay and checked all fuses.
Apr 13, 2011 at 5:37 AM
Advertisement
Avatar
SQM
  • ✓ASE Certified Mechanic
  • 6,383 POSTS
  • ASE Certified Mechanic
Hello,

It sounds like you have a wiring issue for the compressor. As you are able to jump the compressor from the battery, it seems that the compressor is not getting power.
First check to see if there is voltage to the harness that plugs into the compressor.
If there is no power you will have to trace the wiring, as there is likely a short in the circuit.

Here is a helpful guide of testing wires:

https://www.2carpros.com/articles/how-to-check-wiring

I attached the wiring schematics below.

Please let me know of any questions.
Thank you.
Image (Click to enlarge)
Professional Diagram for 2CarPros Members
Click here to log in and view diagram.
Sep 26, 2021 at 9:43 PM
Join 2CarPros for free, one of the most advanced car repair communities on the internet. From first-time drivers to seasoned mechanics, everyone is welcome to reply, share details, and get better answers. You can add a temporary image or video first; uploads are limited to 20 MB.
Ask a Free Question
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.