A/C clutch not working

Good afternoon,

I attached a wiring diagram for the A/C compressor.

Can you remove the relay and with the key on? you should have 2 powers in the connector.

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

Can you verify this?

Can you check for power as well at the high and low pressure switches?

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

Roy

Okay, so with the key on at the relay I do have two power connectors, but as for the high and low pressure switches I have nothing, but when I turn the car on and A/C on I do get a ground at both switches but no power.

The power for the switches comes from the control head. If there is no power, go to the control head and see if the wire, brown, has power when the A/C is commanded on.

If it does, you have a wiring issue, if it does not, then the control head is bad.

Without the signals from the 2 pressure switches, the PCM will not ground the control side of the A/C relay for the compressor to come on.

Roy

The control head would be inside the car right the instrument panel that controls all the A/C stuff by the radio? If so then yea the brown wire isn’t getting no power so that would mean the control head is bad then?

That is correct. That is where the power comes from.

I attached a picture of the control for you.

Roy

Okay, thanks so much for the help. I will go head and replace it and I’ll update it when I do.

You are welcome.

Always glad to help.

Roy

Hey, so I know it’s been a while but I finally had a chance to replace the control head with a brand new one but still the A/C clutch doesn’t engage. I also back probed it to check for power at the brown wire and I still have nothing.

Okay, when you checked the brown wire, was the engine running and the A/C commanded on?

Roy

Yes, I put the A/C on high.

If you disconnect the connector with the key on, does the brown wire have any power?

Roy

No the brown wire doesn’t have any power.

I attached a wiring diagram for you.

check the voltage on both sides of the fuse with the key in the on position.

https://www.2carpros.com/articles/how-to-check-a-car-fuse

Roy

Okay, so I checked the fuses you said to check and they are good. I used a test light connected to battery ground and it lit up on both sides for all of them.

Okay, it is pointing right back to the control head again.

Where did you get the control head?

Roy

I got it at AutoZone.

I would return it for another one.

All tests show it is this unit that is bad.

Roy

Okay, I returned it and got another one at O'Riley’s. I will update when it comes in to see if it’s good or not.

Sounds like a plan.

We will be here.

Roy

Okay, so it came and and I installed it and still same thing I’m not getting power at the brown wire and the clutch isn’t engaging. at this point I’m thinking of just jumping the relay with a jumper wire and leaving it like that, but my only concern is will this mess up the compressor by having the clutch engaged at all times?

It will work as long as you have cold air. The moment it does not have cold air, remove the jumper wire and have the freon system tested for a leak and charged.

https://www.2carpros.com/articles/air-conditioner-leak-detection

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

It will not hurt the compressor.

Roy

Okay, thanks. I will just do that then.

I have another question but it’s about a different car it’s a 2004 Ford Explorer do you think you can tell where the reverse gear signal wire is located at? I installed a reverse back up camera and I need to hook that wire up.

Site policy I can only address one vehicle at a time per question.

Can you please start a new question? The reason being; in order for the site to properly index the questions they need to about one issue/vehicle otherwise people will not be able to find the answer to this question under a different subject. The premise of our site is to assist those that need direct help and also provide a resource for others that have the same issue.

For your convenience here is the link: https://www.2carpros.com/questions/new

Make sure you are logged into the site before clicking on the link

Roy

Okay, will do.