[V70, 1999, 2.5 TDI] Air Conditioning - Compressor does not run

[misha]

No....on the passenger's side....where evaporator pipes goes through firewall....there is a pressostat with 2pin connector... on thicker(low pressure) line.

High pressure line is behind passenger's side headlight and it's a 3 pin connector and switch.

[MichaelPL]

No....on the passenger's side....where evaporator pipes goes through firewall....there is a pressostat with 2pin connector... on thicker(low pressure) line.

Screenshot_2024-09-09-21-47-59-860.jpg

High pressure line is behind passenger's side headlight and it's a 3 pin connector and switch.

Now I understand what you're referring to.
I'll check it and let you know. Unfortunately, this would mean that there is an undetected leak somewhere

[misha]

Evaporator is a weak point on ac system in these cars(p80) because of HVAC system design.

At this age almost all of them already needs to be replaced.

P2 cars don't have this problem.

I replaced mine last year and that was a 3 day job.

[MichaelPL]

That's exactly what I'm worried about

I looked up a tutorial on how it's done, and I'm not surprised it took three days....

[misha]

It's not a hard job,but it's a BIG job and time consuming.

When i was reading a "how to" and what needed to be removed....i didn't felt very well.

[MichaelPL]

There's definitely a lot of work involved with that. It's the kind of job that takes time rather than being particularly difficult.

I checked one more thing yesterday. I connected a gauge to the air conditioning service port, but the compressor was off, and the reading was at 120 PSI.

[misha]

For ac pressure check you will need ac professional gauges...regular gauge will not work for this.
And...pressure is always checked when compressor is running.

Why did you replaced compressor?
Was it seized or leaking?

[MichaelPL]

For ac pressure check you will need ac professional gauges...regular gauge will not work for this.
And...pressure is always checked when compressor is running.

I actually have a Jonnesway gauge set. But you're absolutely right—the result here can be misleading.

[misha]

Is there still 120 psi pressure in the system?
Why the compressor was replaced in 1st place?

Seized or leaking?

[MichaelPL]

Yes, there is still 120psi.

The whole failure started with the compressor seizing. There were visible leaks from it and the air conditioning radiator. A complete new set was installed, including the compressor, radiator, dryer filter, and replacement of the O-rings.

The entire system was flushed clean. The expansion valve was also replaced.