ANY AUTOMOTIVE AC EXPERTS OUT THERE? I'VE GOT PROBLEMS..........

Charrlie_S said

I would have to look up that particular vehicle, but in general a trinary switch performs 3 functions.
1)sor if the refrigerant charge (pressure) is excessively low.
2) shuts off the compressor if the system pressure is too high
3) turns on the cooling fans when the system high pressure reaches a certain level.
How many wires are in the connector for the switch?
I have been retired for some years, so don't have a lot of the manuals on the newer vehicles at home.
Here is a like to the wireing diagram.
All Wiring Diagrams for Toyota Camry CE 1999 – Wiring diagrams for cars

Click to expand...

There are 4 wires on the switch. One circuit appears to operate the clutch, and the other pair appear to operate the fan. With 5 oz in a 28 oz system, the clutch kicks in and runs the compressor steady. When I put in a new switch in anticipation for a recharge, the fans cam on as soon as I turned on the ignition and stayed on. I assume that new switch is faulty as I wouldn't expect the fans to kick in right away as that never happened with the old switch.

I am worried about putting in the old switch prior to the recharge in case that was abnormal for the compressor to run steady and the re-charge doesn't solve the issue. It's costing $$$ to have the system evacuated and recharged each time......Hoping to get it right.

Would 5 oz in a 28oz system constitute: "Shuts off the compressor if the refrigerant charge (pressure) is excessively low"?