Non Working Air Con

[K9d 108]

I've decided to have a look at my 156 air con, 2.4 JTD 10v.

When I press the button on the dash the light comes on, but nothing else happens the compressor clutch doesn't engage.

I checked the fuses and they seem fine, from what I can tell its the 15amp fuse that also does the cigarette lighter socket and that works fine.

I've tried swapping relays, the ones in front of the battery according to the manual it should be front right when looking from the front of the car. When I pulled that relay the car wont start and the same if I pull the relay behind it. According to the manual the rear right is injectors and front right is air con, but both seem to cut the engine out.

Unfortunately the printing on the relay cover is worn away so I can't see whats where

 

I have run a lead from the battery +ve terminal to the connector on the compressor and the clutch engages and it blows cold air.

 

I've checked the pressure on the low pressure side and when the compressor is running its where it should be.

 

Are there more relays that I need to check or fuses ?

[Smaky 73]

If the pressure switch says there is not enough gas in the system then it will not allow the cluth on the pump to be engaged, so the first thing I would do is have the system pressure tested/regassed and then see if it works.