Could someone guide me to the whereabouts of the aircon compressor relay , Aircon not working 12v feed activates the clutch but only 9v feed , I have read a lot about this and cant get to the bottom of my problem . I checked out the switch/sensor on the high pressure line and I get two pins showing 5v and Zero on Brwn/Blck wire Taking the plug off the sensor starts the high speed fan but if I link the Brwn/blck to Blck/gry the fan stops . The only other wire is Grn/yellow which hods 5.0v So three wires in total .(trinary switch perhaps)?
Not quite sure whats going on here but I suspect the compressor relay at fault . Can anyone help please.

Is the compressor drive belt intact? Just a thought!
Usually it's down to low refrigerant.
Looking at the circuit diagram the compressor is feed directly from the ATC module.
The green yellow is the feed to the pressure sensor 5 volts, the black slate wire is the sensor return signal 0 to 5volts I would recon 2-4 volts would indicate pressure in the system, and brown black is the ground 0 volts. you will have to check the voltages with the sensor connected to get true readings.

Hope that helps you.

That’s great , .... progress , I’ll rig up some test for that, what is throwing me is the Gap tool is telling me I have 5.33 bar ehich I don’t believe or it the sensor that’s faulty killing the the feed to the compressor, in any case if the compressor is idle the the values in either line should be equalised at the moment due to the fact that it’s not working . Post later . Cheers pat
To add to that I am interested to know if I can override that sensor to trigger the sensor . There must be a relay but according to Rave , as you say he acknowledged controls this , unless there is a relay there ? Can’t see it on Rave.

What I meant in the last reply was , As you say the sensor seems to control the compressor to go off and and on. Was thinking if I could hot wire this.Cheers

Stevie_b wrote:

Is the compressor drive belt intact? Just a thought!
Usually it's down to low refrigerant.
Looking at the circuit diagram the compressor is feed directly from the ATC module.
The green yellow is the feed to the pressure sensor 5 volts, the black slate wire is the sensor return signal 0 to 5volts I would recon 2-4 volts would indicate pressure in the system, and brown black is the ground 0 volts. you will have to check the voltages with the sensor connected to get true readings.

Hope that helps you.

Do you have access to normal gauges to compare the IID tool reading with.

This would tell you if the pressure sensor is knacked.

A known full charge and static gauge pressure (assuming the compressor clutches in) points towards a faulty swash solenoid within the compressor. 2007 3.6 TDV8

Yes I might do that to compare, let you know.

Ok put my manifold gauges on and there is no pressure , so to that end a good recharge shoud do it ......with some leak stop!

Stop leak or a new condenser maybe ?