My AC was working one day and not the next. R134a pressures look fine at rest using manifold gauges, so I don't think it's a leak. The compressor clutch does not engage. It does engage if I manually give it 24v from the truck batteries. That pushed my attention to the low pressure switch or electrical connection to the switch.
The part I'm concerned about is that when I unplug the connector to the low pressure switch and jump the connection with a paper clip, the clutch still doesn't engage. The connector does show 4.95v on the multimeter. I don't know what is on the other end of this that might be malfunctioning. It's in the dash, so I hope I'm just performing this test wrong and the problem is actually the pressure switch.
If it does turn out to be the pressure switch, it looks like the refrigerant has to be drained because there is no Schrader valve/O-ring setup on it. Can anyone confirm that? I started to unscrew it but heard the R134a escaping, so I assume that it has to be vacuumed to change it out.
One more thing - the switch part # is RD-5-9165-0. Is there a good way to source this or an equivalent? I'm only seeing the whole AC package out there.
![Capture.jpg Capture.jpg](https://www.steelsoldiers.com/data/attachments/528/528854-8d9640080903cab543bb1433aec6128d.jpg)
The part I'm concerned about is that when I unplug the connector to the low pressure switch and jump the connection with a paper clip, the clutch still doesn't engage. The connector does show 4.95v on the multimeter. I don't know what is on the other end of this that might be malfunctioning. It's in the dash, so I hope I'm just performing this test wrong and the problem is actually the pressure switch.
If it does turn out to be the pressure switch, it looks like the refrigerant has to be drained because there is no Schrader valve/O-ring setup on it. Can anyone confirm that? I started to unscrew it but heard the R134a escaping, so I assume that it has to be vacuumed to change it out.
One more thing - the switch part # is RD-5-9165-0. Is there a good way to source this or an equivalent? I'm only seeing the whole AC package out there.
![Capture.jpg Capture.jpg](https://www.steelsoldiers.com/data/attachments/528/528854-8d9640080903cab543bb1433aec6128d.jpg)