Aircon on R32 - No power but?

[Strexx]

So I've had a hunt around these forums and can't really find an answer:

My AC control unit will not power up - well there is no LCD activity - in fact there is nothing, however - There is an aftermarket switch on the dash which does power the unit up - well the lamps/leds on the fan and the recirculate button illuminate.... and nothing else. The unit blows air and I feel that it was getting cooler at one stage but then it just blew warm - I will check the ambient temp sensor on the centre console to see if that is connected. At one stage when I pressed the Econ  button and then went back to the AC button, I could hear strain on the motor as if the AC pump had switched on but I could not replicate it all the time.

Are there any typical issues with the AC unit not displaying anything on the LCD panel?  What a fix?

I'd assume it needs a regas - but is there anyway to confirm?

Any advice would be appreciated.

[djr81]

Search mode door actuator.  Also blend door.  Mostly blend door.

[GTSBoy]

I'd say he's got bigger problems than the blend door though....

[djr81]

Well I reckon he has too but the three or four things I would start with are:

Check power supply to control unit and any other oddball modified shit someone may have done be it there or elswehere.

Change out control unit with a known good one.

Check blend door.

Check mode door.

Ofcourse that is assuming the Humphrey B Bear has refrigerant in it and the compressor etc goes round.

[Strexx]

Thanks for all the advice - I'll try to get to it over the weekend - Hey is possible to buy a kit to regas your own AC or do I need to have it done?

How can you check to see if you need a re-gas?

[GTSBoy]

9 hours ago, Strexx said:

Hey is possible to buy a kit to regas your own AC or do I need to have it done?

How can you check to see if you need a re-gas?

No, you can't. Just take it to an air-con shop and get it checked and/or fixed. But note that they cannot do it unless it is actually a working system! You need to be able to run the compressor to check the system pressures. If there is no gas, then your pressure switch will keep the compressor from starting, but you sound like you have a lot more work to do first.

[Strexx]

I had a win and got the AC head control unit working again - So there was no activity whatsoever of the control unit - No LCD and the buttons worked occasionally but you never got feedback to know what the buttons were doing. So I pulled the centre console out and then pulled the AC control out and spent ages trying to pry out the cable connectors at the rear with no success. Simply could not get them out of the unit.  So I stuck it back in and then proceeded to remove the stuck on facade.. This was stuck on with double sided tape so I gently eased it off. There were then three screws to remove in each corner - with these removed and a little prioring of the clips around the edge, the front LCD display and circuit board pops off.  Where the horizontal circuit board join the other LCD vertical  board - there are about 20 pins that slot into the board to make contact.   These were simply corroded or tarnished enough that there was no connectivity. I gently rubbed the pins with some very fine wet n dry - You could see the dust/corrosion coming off in the sunlight - I sprayed them with some electrical contact cleaner and put the two boards back together screwed it up and turn on the ignition to test and hey presto all the LCD came alive and every button cycled through it expected mode - So I put the centre console back (Saw the radio retro fit which was shite - but I'll fix that up next) In changing modes the levers move and open close the door actuators & blend doors - they are bit stiff and make a groaning noise but they all seem to work as expected. It heats and I'm sure the AC needs a regas for cooling - but it works as expected. I hope that this helps some one else with a fix.

[GTSBoy]

Good work.

FWIW, the loom plugs on the rear have little tangs that you have to squeeze inwards to get them to release.