Intermittent A/C problem on W203

[KLP 92]

Update

I tried having the system drianed, cleaned with nitrogen and refilled twice but had no effect. The A/C was still intermittent.

There is what MB say is a temperature sensor at the bottom of the condensor. I purchased one of these and changed it as the one on mine had split in two, and the circuit board was exposed but intact.

Anyway, fingers crossed and frantcially touching wood, the car has been fine for the last 2 days and has worked everytime.

May be unrelated but they A/C drainage hose had a knot in it near the transmission tunnel for some odd reason causing a leak at the top of the pipe which kindly drained into my footwells. Anyway, all probs now rectified with an ice cold A/C!

 

[BlackC55]

I tried having the system drianed, cleaned with nitrogen and refilled twice but had no effect. The A/C was still intermittent.

There is what MB say is a temperature sensor at the bottom of the condensor. I purchased one of these and changed it as the one on mine had split in two, and the circuit board was exposed but intact.

Anyway, fingers crossed and frantcially touching wood, the car has been fine for the last 2 days and has worked everytime.

May be unrelated but they A/C drainage hose had a knot in it near the transmission tunnel for some odd reason causing a leak at the top of the pipe which kindly drained into my footwells. Anyway, all probs now rectified with an ice cold A/C!

Thats the Evaporator temp sensor I believe. A star machine would have picked this up with some live data readings.

Glad you got it sorted

 

[KLP 92]

Thats the Evaporator temp sensor I believe. A star machine would have picked this up with some live data readings.

Glad you got it sorted

The only diagnostic fault code was the one saying the refrigerant pressure was too low. There was enough gas in the system so it wasn't a leak causing the prob so could be down to an intermittent fault on the compressor or a faulty sensor.

According to MB there are no pressure sensors on the EPC at all for the entire A/C system, just 2 temp sensors, one on the evaporator and one on the condensor.

I presume the temp sensor may be a pressure sensor as i has 4 pins and upon stripping it down has a small circuit board containing a good 15 components. I changed the condensor one first as it the easiest one to do.

The evaporator sensor is located behind the dashboard and is a pig to change, so i really hope that its cured! And if it isn't that then i have the lovely job of buying a new compressor. Fingers crossed!