Actuators

Hi Carguy,

There are a couple main reasons the compressor doesn't come on. However, first when you say bad actuators, are you referring to the blend door, mode door, re-circulation door in the HVAC housing? If so, even if all these are not functioning it will not prevent the compressor from coming on.

Here are a couple of guides that will walk you through the basics. The most common cause is low Freon. If it is too low, the PCM will not allow the compressor to run because it will damage it.

Next is if you are not getting power or ground. Like if the relay/fuse is bad.

Give these a look and let me know what you find. I would start with putting a gauge set on them and seeing what your pressure is.

https://www.2carpros.com/articles/car-air-conditioner-not-working-or-is-weak

https://www.2carpros.com/articles/air-conditioner-how-to-add-freon

Let me know and we can go from there. Thanks

Is not low on Freon.

Okay. So the other main causes are no power to the compressor or it doesn't have a ground connection. The other main cause of it not coming on is it has just failed. However, to answer you question assuming you are talking about the actuators that control the air flow and temperature inside the vehicle, they do not prevent the compressor from coming on.

Best thing to do is check for codes and then test power and ground to the compressor. Let me know what you find. Thanks

Could it be the relay under the hood?

It could be if you don't have power to the compressor. I included a wiring diagram. You will see in the top right corner is the relay that is a direct feed to the compressor. You should have power on this wire with the engine on and AC turned on. If you don't have power then the relay could be the cause.

I had the issue of the compressor not coming on. Bypassed the relay and the clutch activated. Bought and changed the compressor, brought it in and had a vacuum set and added Freon. Replaced the relay, still nothing. Then replaced the pressure sensor switch. Nothing. I turn it on, and I get hot air. Could this be the ground or is there another reason causing it not to turn on?

Hi,

Is your vehicle the same year, make, model, and engine size as the original one listed at the top?

Let me know. As far as the compressor, if you were able to actuate the compressor clutch by jumping power at the relay, it sounds like the relay's primary side isn't getting power to actuate the switch.

Let me know. Also, if your vehicle is different than the original one, I will need you to start a new thread. We do that so it is more helpful to others. All you need to do is copy and paste your question and add the correct vehicle info. Here is the link for a new post:

https://www.2carpros.com/questions/new

Let me know.

Joe

When I apply 12 volts to pin 87(relay removed), the clutch engages. If I wrap a small wire around relay spade 87 and insert the relay then get power at the small site the the relay would be good?