Climatronic A/C

[Long in the tooth]

Hi guys

My Climatronic a/c is poorly : have reason to suspect evaporator temp sensor is faulty and sending wrong info.

I believe evaporator itself to be behind dashboard ? (true or false?)

In any event can anyone help with how best to access the temperature sensor as I intend to replace it.

Many thanks in advance

[dilksie]

Have you had it checked with VCDS? If not then this will be your best bet as it will be able to check everything in the system and give output readings.

[Long in the tooth]

22 minutes ago, dilksie said:

Have you had it checked with VCDS? If not then this will be your best bet as it will be able to check everything in the system and give output readings.

Yup : did a while back : didn't reveal any 're-portable' discrepancy/inconsistency in a/c system : but system still has an annoying problem : all's well for 30 to 45 minutes then a/c output fails - fan output fails across all vent outlets (suspect evaporator is frozen up?) : switch off for 5 to 10 minutes then all's well for the next 30 minutes or so until problem repeats itself.

Car has recently had refrigerant top-up/refill : new heat exchanger radiator.

[Longship]

Got a very similar problem with mine. On long journeys, I've noticed fan output dropping off and car steaming up. I can turn fan up to max and hear the fan roaring but no output anywhere. A short period of off seems to reset system.

[Long in the tooth]

3 hours ago, Longship said:

Got a very similar problem with mine. On long journeys, I've noticed fan output dropping off and car steaming up. I can turn fan up to max and hear the fan roaring but no output anywhere. A short period of off seems to reset system.

 

Hi Longship = have you had the system diagnosed, or do you have a sense of the cause ?

[Breezy_Pete]

There's a measuring block that VCDS can log, while you're driving, called Compressor shut-off code. It would probably help solve your problem if you could correlate the loss of cooling with a non-zero code appearing in this measuring block. (zero translates as compressor running, other codes defined e.g. here).

[Longship]

I don't have Vcds but Carista hasn't picked up any fault codes. It was only noticed on my last long trip (9 hours each way) Seems to occur after approx 4 hours of driving. I'm due another journey soon so I'll monitor the ventilation closely.

[blackspaven]

To your original question, but I think what you're asking for the position of is easily accessible behind the dash: If you pull off the top cubby hole bit, there are two sensors that do a 90 degree screw out either side of the heater vents at the back of the aperture. Grey plastic topped I think, but from memory you should see them as pretty much the only things in the top bit with a wire/s going to them. I swapped mine around when trying to find a fault as if only one side is working then swapping them would make the other side work if it was faulty. Hope that helps.

[Longship]

I think I may have got to the bottom of my issue. The ventilation recirculation motor may be playing up. Did a longish trip yesterday and as usual it started out fine but then the vent stopped working. Fan was working, just no output. A long google search brought up that the recirc flap closes when the washers are used. It looks like I need a new V71? Motor. In the meantime I'll set the vent to fresh air inlet and unplug the motor.