I have what appears to be an electrical fault on my 2010 Ford Galaxy. The gas pressure has been checked, the pressure sensor has been replaced and if we 'bypass' the aircon relay, the clutch engages.
I need some help in troubleshooting what the issue could be.
Hello, I hope the following assists you.
The air conditioning clutch is controlled by the engine management (PCM) if certain faults are detected then it won't allow the air conditioning to turn on.
There are a couple of common concerns that stop the air conditioning working on this model.
If the pollen filter has been replaced recently make sure the evaporator temperature is still connected, the wiring to this sensor comes across the pollen filter housing and disconnecting the sensor makes it easy to get the pollen filter out. The sensor is on the left hand side of the heater box in the footwell.
If there is a problem with the cooling fan the PCM can detect this and again won't allow the compressor clutch to engage, it's common for the wiring in the engine bay to corrode stopping the fan from working so check the cooling fan operation and if necessary check the control wire continuity between the fan and PCM and the air conditioning relay in the fuse box to the PCM wiring. The age of the car doesn't matter with regard to the wiring corrosion, this has occurred on 12 month old cars and is well known to Ford that they issued a technical bulletin to dealers to alert them to this.
Start with these points, let me know if I can advise further and I'll reply as soon as I'm able to.