Hello forum. Back with another AC project. 2000 Mitsubishi Montero Sport 3.5L 235K miles. Vehicle was purchased 8 yrs ago with inop AC. The owner (Uncle) took it to a shop 7 yrs ago to have the AC repaired. A new compressor, drier and exp valve installed. AC worked ok for a brief period then quit. N...

New switch is in and system recharged. Was unable to obtain a 210 psi on the high side to determine if the new switch signals the fans to “high”. Apparently that part number serves three switches, and the first one I ordered albeit identical in all regards, would not accept the electrical connector ...

John for the win. There was a Schrader valve under the switch. I discharged and left about 10 psi in the system. Removed the switch and low and behold there is a Schrader valve hissing at me. I took pick pics of the switch to get part a part number. There was an O-ring on the Schrader body which was...

Red line is pointing to a mating surface. Yellow line is pointing to the boss which the switch mounts. The blue is pointing to the base / female fitting of the switch. The switch was sending a high pressure signal (verified with scan tool) which was commanding both fans to max in every “key on” situ...

Pic. Had to resize

I took a pic, but is too large to upload here. I’m struggling to find a part number for that switch, so I was going to remove, inspect and or take to the parts house in hand to compare to the replacement, As mentioned I got 4-5 turns on it before it began leaking, which is ample to have a leak. It a...

Ok. Went to pull the high side fan pressure switch. Unscrewed it about 4 turns and it started hissing. Waited a moment and it started hissing heavier and would not stop, so screwed it back down. Sealed up.

Is there a Schrader valve under there? The mounting flange doesn’t look very deep.

Yes. I watched that blend door actuator (both of them) for 10-12 cycles with no anomaly. Then it went from hot to cold and stopped about 3/8” shy of full cold. Then that was its range for several cycles before returning to normal. I was going to ask if there was a valve under that press switch. Than...

Just posting a follow up for posterity. Had a cooling fan issue (fans on high all the time) and the scanner live data showed a AC PRESSURE - HIGH. (Key in, engine off, AC not run). After several days of having the fuse for the fans pulled I took the car to a mechanic with a GM TECH2 scanner. Put the...

It was a “Dry Cold” up north at least!