LouZ

Decided to recharge it today, so the first thing I found was that the compressor didn't engage. The volt meter showed no voltage. I figured it was low on pressure. So I hot wired it and the compressor turned. I then charged it so that there was 45 psi on the gauge.

It was blowing cold so I shut down and unhooked the hot wire and plugged it back to the feed wire.

Well, it still doesn't engage, fuse in engine compartment is ok, the front fan runs, so now, I need to sort out why it's not powering up!

power_up

Pressure switch give no signal to engage the compressor?

LouZ

Where is the switch located?

power_up

The pressure switch beside the expansion valve. Item 11 in pet

911PERVY

Is the relay working?

ToreB

The compressor activation signal (GND) is generated in the CCU, and shut off by the ("three level")pressure switch if the pressure or refrigerant level is too high or too low.
The +12V feed for the compressor relay is routed through the R01 Backup Light relay in the front fuse box.
See the my HVAC pages (select the Details page) how to find faults in this: www.porschehvac.bergvill.com
Cheers,
Tore