Hi all . Since owning my Vrs I've had no aircon .. The ac and recirc light only comes on if the fan is on 2 or more . But no ac .. I've had it scanned and it has 1 fault .. V154 . My mechanic friends says he don't think that would stop the air con working . Any ideas ?? Also how can I fix the v154 fault

Regards Tony

When was it last regassed?

 

Does the compressor (not the drive pulley) turn over when you switch the (presumed manual) a/c on?

V154 is the recirculation flap motor in the air distribution plenum, it's probably stuck or the motor has failed, as your friend stated it won't stop the aircon working though.

 

Get the aircon system degassed, checked for leaks and regassed.

It was gassed before I brought it . 12 months ago .. When you press the ac button . No change in engine note .however as I've never had a car with ac I'm unsure what I should be hearing . I do know that the ac and recirculating buttons only light up orange now and again !!

That sounds electrical, probably intermittent contacts at the backs of the switches because the telltales are direct earth rather than inline to the pump and flap motor.

 

So another question; when you press the AC button does one of the radiator fans run on slow?

I will have to check the fans .. Will do it tomorrow night when I'm with the car .. Seems funny that the ac and recirc buttons only work on fan speed setting 2 or above . Is this normal ?? And when I do press the buttons nothing seems to Happen . No flap noise or engine note change .. I may sound stupid here but I don't really know how the aircon works . The compressor is driven from the Alt belt .. But that's all I can see . Anyway off testing the compressor ??

Does speed 1 actually work/blow air on the cabin fan? Common for the series resistor to fail.

 

My recirc flap motor on the Polo is highly temperamental, and the light on the switch doesn't illuminate except when the flap is in co-operative mood.  Doesn't affect the AC at all though.

 

There is an electrical signal that goes to the compressor, I think via a two-pin brown plug/socket on the same bracket as the notorious alternator signal wiring on the front of the gearbox, so worth looking for busted wires down there.

The compressor spins all the time and has a shear clutch if it seizes so you can't tell if it's working or not simply by looking at it.

 

Suspect your fan speed resistor pack may be failing, it sounds like you've lost speed 1 already.

 

The engine cooling fan should come on with the aircon, if not then you may have a failed cooling fan.

Right I've had a poke about under the bonnet .. Turned blowers on 3 and pressed the ac button . Looked under bonnet and no fan on .. Could this be why the ac don't work . Not managed to check if the compressor has power as I left my multimeter at work

I think it's probably the other way round, the fan's not going because the AC isn't being started up.

I think you'll see visually if the AC wiring is intact or not at the plug/socket connection mentioned, no real need for meter. Pop a couple of wheels up on a kerb, remove engine undercover and have a look.  I'm struggling just now to find a good photo. Front of gearbox brown connector pair IIRC.

Agreed about the interior fan resistor pack, but that shouldn't affect the AC when the interior fan is running.

 

Which, logically, takes us to the AC. I agree the wiring could be the problem as Wino suggests, or it could still be the AC clutch. If that fails, the pulley will still spin, but the shaft at the back of the compressor won't. These are both visual checks and need access to the car.

Is there anyway I can give the compressor 12v to see if it kicks in ??

Agreed about the interior fan resistor pack, but that shouldn't affect the AC when the interior fan is running.

 

Which, logically, takes us to the AC. I agree the wiring could be the problem as Wino suggests, or it could still be the AC clutch. If that fails, the pulley will still spin, but the shaft at the back of the compressor won't. These are both visual checks and need access to the car.

See posting #8 - these compressors are driven continuously but when not required, run on a very low duty cycle, again, as posting #8 said, if the compressor seizes internally, a shear coupling on the pulley will fail and allow the remaining auxiliary bits to get driven. IE no clutch involved with the benefit of some oil being dragged around the system all the time to keep the seals happy.

Edited 29 July, 201510 yr by rum4mo

It was gassed before I brought it . 12 months ago .. When you press the ac button . No change in engine note .however as I've never had a car with ac I'm unsure what I should be hearing . I do know that the ac and recirculating buttons only light up orange now and again !!

My mk 1 fabia aircon and re circ light both come on but it must need re-gassed as the cool air iam meant to get is very poor. Kwik fit have said they will check the compressor and re gas if needed for around 35 quid ish... which i find quite cheap actually

My mk 1 fabia aircon and re circ light both come on but it must need re-gassed as the cool air iam meant to get is very poor. Kwik fit have said they will check the compressor and re gas if needed for around 35 quid ish... which i find quite cheap actually

I'd agree, KwikFIt use an automated system that even they can't mess up, and I think still do "colder afterwards or you don't pay".

What happens if it's a slow leak though? Will they still fail it based on that or won't it notice the pressure drop?

What happens if it's a slow leak though? Will they still fail it based on that or won't it notice the pressure drop?

You don't normally do a pressure (or leakdown) test first. You drain the system, and weigh the gas drained. Then do some sums based on time since last filled to determine whether or not there is a leak or just normal loss.

I think that as normally there is no credible history of an car's A/C system, after the charge is recovered (and weighed), the system is placed under a vacuum for a period of time related to the system under test type, this does two things, it removes any moisture remaining in the system - and any remaining fridge gas except some that will still be in the oil, and it allows the gas recovery machine to establish if the system is leak tight enough to recharge. A failure to pull a target level of vacuum in that period or time should stop the process dead as the system is not fit for charging. Edit:- at that point a proper fridge person would carry out a pressure test with Nitrogen gas, or maybe even Helium and if a small charge of R134a was added back in before pressurising with Nitrogen, a sniffer would be used to locate leak sites - but in reality, there must be a balance between cost and environmental issues it seems, so some cars will be returned with leaks.

Edited 31 July, 201510 yr by rum4mo