Replacing AC Thermoswitch
 

My AC thermoswitch is balky and needs to be replaced. According to the FSM, the evaporator should be removed to replace it (which involves removing the dash and evacuating the AC system) and I don't want to go there.

The switch itself is easily reached after removing the glovebox but the temperature probe attached to it is routed into the evaporator and is not easily accessible. I could possibly remove the existing probe by just cutting it and yanking on it but I am not sure it would be possible to get a new probe routed properly from the glove box entrance. Anybody managed to do this? (I guess another possiblity would be to leave the probe in place and attach it to the new thermoswitch.)

Bump for me.

had mine done in car without removing dash 35.00 for aftermarket switch total cost 170 at ac shop ,it can be done

That seems like a high labour cost. Did it involve evacuating the AC system and then recharging it?

If you didn't have to remove the dash it's cheap at twice the price.
Thanks for the useful info. I'll keep it in mind if mine goes bad.

You don't need to remove the dash to get the evaporator out; only the glove box. I've done this and it's actually a lot easier than it looks. 2 nuts under the dash and it slides right out. I couldn't believe it. The most difficult part is getting wrenches onto the refer fittings in the engine compartment; looks tough, but it can be done. Whole thing took less than 30 minutes.

Note that it is not possible to remove the existing probe while unit is installed--there is a plastic wedge clip that secures it in the evaporator. A replacement probe must be in contact with the evaporator (not just in the air stream) as its job is to prevent freezing. Good contact is essential.

Thanks - this is the information I was looking for. Is it possible to leave the probe in place and attach it to a new thermoswitch? (Probably not I would guess.)

My switch also went bad (AC was intermittent because switch has high resistance when closed) and I got the same info about the big job to replace it. I ended up just jumpering the switch but have to manually cycle the compressor with the "AC" button - PITA. I will be watching to see how this turns out.

If my AC goes on and off then it is most likely this thermoswitch? I have a PFC, but I dont think its the PFC that is causing it since it goes on and off almost regularly.

It could be, but another possibility is the pressure switch, which will stop the compressor engaging if the pressure in the system is too low (which could be caused by a low freon level). You can jump both of these switches in turn to determine which one is the culprit. (The FSM has instructions on how to do this.)

Note that the thermoswitch is intended to cycle the compressor, particularly at lower fan speeds to prevent the evaporator from getting to cold and freezing up. If the thermoswitch fails in an open condition due to a dirty contact, then your A/C compressor will not come on at all, or will be unpredictable and unreliable. If the compressor runs, but there's inadequate cooling, that will be another problem (not the thermoswitch).

The thermoswitch probe and switch itself are one hydraulic unit and cannot be separated. I think it is possible, if you are very careful and adept at these kind of things, to dissasemble the switch while on the care and clean the contacts. I repaired my switch while it was off the car and reinstalled it. It works fine. Just be sure to seal it up real well to keep mositure out, as it could condense inside the switch and cause it to fail--again.

how did u repair the switch? just clean it?