AC not working

[MissSpentYouth]

Hi I have a 2014 volvo v40 D2 in which the AC has stopped working.

The system has been regassed so all good there if I jump the pins on the AC relay the compressor spins up and the AC all works fine nice and cold.

Checked out the wiring and tested for continuity from the AC relay back to the ECU and all good. I have +12V on one side of the relay coil as per wiring diagram but the ECU just doesn't pull the other side down to operate the relay.

Only fault code I am getting is for the power operated flaps in the front grill tested them all out and they seem to be working fine though

Does anyone know what things the ECU uses to control the AC firing up ?

Ambient air temp above 4 degrees
Refrigerant pressure above a certain minimum threshold
AC button pressed and light on
Internal fan above a minimum value
Engine running

Any more

What about these power operated front grill flaps it is moaning about could that stop it engaging AC

Any help appreciated

cheers

Ben

[Clan]

Originally Posted by MissSpentYouth

Hi I have a 2014 volvo v40 D2 in which the AC has stopped working.

The system has been regassed so all good there if I jump the pins on the AC relay the compressor spins up and the AC all works fine nice and cold.

Checked out the wiring and tested for continuity from the AC relay back to the ECU and all good. I have +12V on one side of the relay coil as per wiring diagram but the ECU just doesn't pull the other side down to operate the relay.

Only fault code I am getting is for the power operated flaps in the front grill tested them all out and they seem to be working fine though

Does anyone know what things the ECU uses to control the AC firing up ?

Ambient air temp above 4 degrees
Refrigerant pressure above a certain minimum threshold
AC button pressed and light on
Internal fan above a minimum value
Engine running

Any more

What about these power operated front grill flaps it is moaning about could that stop it engaging AC

Any help appreciated

cheers

Ben

Yes it will not turn the AC on if the cooling air flow for the condenser has a fault code ..

[60041]

Air con on our V40 stopped working when the radiator fan packed in.
The dealer said that they had come across the problem before.

[MissSpentYouth]

Thanks Guys.

Yes indeed the main engine cooling fan was not working that was why the AC was not working.

The Fan controller has 3 wires going to it at the radiator. With the ignition on the 2 big wires have +12V and Ground and there is a skinny purple wire that goes to the ECU that takes a digital signal. This wire was open circuit oddly. There was no visible signs of any damage to the harness or connectors but was open circuit.

I jumpered a fresh wire between the ECU (pin B14 from memory) and the fan controller and now both Fan and AC working great.

Weird fault on such a new car with no visible damage to loom, maybe a poor connection under the fuse box to blame though I think it is just a straight piece of wire.