A/C not working?

Hi,

Fuse 10 will only have power when the relay is actuated. So, something is preventing that from happening.

I attached the wiring schematic below of the A/C clutch circuit so that you have a reference.

Okay, at the relay, there is a primary and secondary side of the relay. On the relay itself, you should see each pin is numbered.

The primary pins are 85 and 86. The secondary side are pins 30 and 87.

First, identify the pin locations. Take a test lamp and with the key off, check pins 30 and 87 for power (secondary side). One should have power at all times and the other won't.

Next, turn the key to the run position (engine off). Check pins 85 and 86. One of those two should have power with the key on.

Note: I can't tell you the power supply pins because the manufacturers do it differently.

If you find that both the primary and secondary sides have power, then the problem is the primary side ground, you already jumped the relay and the compressor engaged, so that tells me you will find power on the secondary, and the power wire to the compressor is good. I feel confident the problem is the primary side.

If the primary has power with the key on, check the opposite side of the primary for a ground path when the A/C is requested on. To do that, connect your test lamp alligator clip to the battery positive and probe the primary, relay ground pin. With the key on and AC requested, the test lamp should turn on.

Note: The ground path is supplied via the PCM. See pic 2 below

Let me know what you find or if you have questions.

Take care,

Joe

See pics below.

I think I found the ground that you were talking about, it was under the coolant reservoir. I cleaned it off and put a test light on it appears to be a good ground. But I still have no power to the 10-amp fuse nor does the clutch engage unless I jump it. Again thanks for your help.

Hi,

As far as the fuse, you won't have power until the secondary side of the relay closes. Were you able to check for a ground signal on the primary side? If you look at the pic I attached above, the green wire with a white tracer goes to the PCM for a ground. That has to happen for the secondary side to close and for power to reach the compressor.

Take a look at this link, it explains how the relay works and what to check for:

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Let me know. Also, let me know if you have other questions.

Take care,

Joe

If I am reading your diagram right, the green with white tracer is grounded on the left front fender well under the coolant reservoir. I checked that ground and it appears good. I also followed that video you sent me; I did test the relay and it works. Again, thank you and thank you for your help.

Hi,

With the A/C on and the vehicle running, carefully check to see if there is power to the compressor. If the relay is working, there should be power to it.

Let me know.

Joe