Air con help needed please

[jucam61]

Hi
I am new here so please excuse any errors in posting .
I have a Multispace desire with a problem with the air conditioning or rather with the compressor not activating in positions 3 and 4 on the blower .If I turn fan onto position 1 or 2 and switch the a/c on it works fine but if I increase the blower speed the compressor switches off until the fan is back in position 1 or 2 .  The system is fully gassed and working normally in every other way  and the heating and fan all work normally . I was wondering if it could be as simple as the fan switch itself but thought I would post this and see if any other members had any ideas  please .

[polar]

All i can advise is check the cooling fan is working on speed 3/4 as it should do if it does not it could be a faulty cooling fan or relay? Ive no idea past this really.

[jucam61]

Thanks but everything is working as it should apart from this annoying glitch .You can actually hear the compressor switch in and out as the fan speed changes . if yo put fan switch on 3 or 4 before switching on a/c it does not start up if you have it on 1or 2 it kicks in compressor but if you then turn fan to 3or 4 it will cut compressor again until you return to 1 or 2 . I am not very good at reading car wiring diagrams as I have had it to easy with the motorcycle ones so not sure if it switches the compressor with a live or an earth or if it goes through a module even . I only noticed it because the A/c got warmer with the higher fan speeds so got it checked for gas etc and found this was happening .

[brajomobil]

Thanks but everything is working as it should apart from this annoying glitch .You can actually hear the compressor switch in and out as the fan speed changes . if yo put fan switch on 3 or 4 before switching on a/c it does not start up if you have it on 1or 2 it kicks in compressor but if you then turn fan to 3or 4 it will cut compressor again until you return to 1 or 2 . I am not very good at reading car wiring diagrams as I have had it to easy with the motorcycle ones  so not sure if it switches the compressor with a live or an earth or if it goes through a module even . I only noticed it because the A/c got warmer with the higher fan speeds so got it checked for gas etc and found this was happening .

Like Polar said if your blower is working ok with NO a/c then you have to
connect your car to lexia and check a/c pressure and a/c sensors.

Best regards,
brajomobil

[paddlesat16]

I don't think lexia can tell A/C Pressure you will need aircon manifold gauges for that. The car is probably low on aircon gas and will need a refill. The thing with aircon is it needs to be used all year round and not just in the summertime the gas has a tendency to leak away out of the joints if not used.

Regards

[brajomobil]

I don't think lexia can tell A/C Pressure you will need aircon manifold gauges for that. The car is probably low on aircon gas and will need a refill. The thing with aircon is it needs to be used all year round and not just in the summertime the gas has a tendency to leak away out of the joints if not used.

Regards

Lexia can show A/C pressure. It does on my 1.6HDI 2008.

Here is pic from another forum for C3. It is low resolution but you can see "Air conditioning pressure" -> 7 bars
   

Best regards,
Brajomobil

[jucam61]

I don't think lexia can tell A/C Pressure you will need aircon manifold gauges for that. The car is probably low on aircon gas and will need a refill. The thing with aircon is it needs to be used all year round and not just in the summertime the gas has a tendency to leak away out of the joints if not used.

Regards

Lexia can show A/C pressure. It does on my 1.6HDI 2008.

Here is pic from another forum for C3. It is low resolution but you can see "Air conditioning pressure" -> 7 bars


Best regards,
Brajomobil

[jucam61]

Thanks for the info and advice .I have had system refilled by specialist and everything is ok except the aircon switches off in position 3 and 4 on the fan or rather the compressor clutch cuts out [freewheel ] switch stays lit .Turn the fan back to 2 and it cuts in again . Same on the other side of fan switch {recirculation]. Temperature is icy cold so I can live with it if needs be but would like it to work as it should . I have checked switch for contacts and all seems ok . Can anybody tell me where the relay is located please ? I do use aircon all year round for demisting etc so I am pretty sure it is electrical rather than a low filled system . It did the same thing before I had it regassed and it while it was regassed that we noticed the problem . I thought the aircon was low because it was not cold on the high fan speed . I had never used it on the lower speeds much before but I swithed it on to one so I could hear if compressor cut in and that's what I found .
Best Regards
Julian

[jucam61]

Thanks but everything is working as it should apart from this annoying glitch .You can actually hear the compressor switch in and out as the fan speed changes . if yo put fan switch on 3 or 4 before switching on a/c it does not start up if you have it on 1or 2 it kicks in compressor but if you then turn fan to 3or 4 it will cut compressor again until you return to 1 or 2 . I am not very good at reading car wiring diagrams as I have had it to easy with the motorcycle ones  so not sure if it switches the compressor with a live or an earth or if it goes through a module even . I only noticed it because the A/c got warmer with the higher fan speeds so got it checked for gas etc and found this was happening .

Like Polar said if your blower is working ok with NO a/c then you have to
connect your car to lexia and check a/c pressure and a/c sensors.

Best regards,
brajomobil

[jucam61]

Hi
Thank you to everyone for your advice .Just to let you all know that this is now fixed . I replaced the fan unit resistor with a new one as I had tried everything else and it now has the compressor working in all four speeds . The heater fan itself runs perfectly with the old unit so I can only presume the resistor provides an earth somehow for the compressor . Many thanks everyone .
Best regards
Julian