A/C problem 1990 Legacy

[Kenneth1948]

A/C was not working although still had some charge. Removed compressor, drained oil, replaced with ester oil, flushed, vaccumed and charged with R 134. Still not cooling.

Technician performed analysis, says it needs new expansion valve (readily available and not expensive)

and: Evaporator temperature switch

or Evaporator Thermal switch.

Have searched usual parts sources and found this part OEM # 7307 1AA020 from one source at $ 73.00

Can anyone recommend an aftermarket part source that may be less expensive. 

• I am not familiar with this switch, is it a common problem?
• Would a used switch be a good option?
• How do you test it?

Probably enough questions for this post. Any tips or information would be appreciated. John aka Kenneth

[Legacy777]

Yes, I have read whether others have had to replace that evaporator temperature switch.  I am pretty sure they got the switch from the dealer.  If the system is already pressured up, you can cut the wires going to the controller unit on top of the evaporator box and splice the wires into the new controller unit.  Make sure to note the orientation of the wiring if you do this.

 

You could try a used one if you can easily find one.

 

Is the compressor kicking on at all, or is the compressor running and it's just not cooling?

[Kenneth1948]

I'm in a situation I hate to be in, it's my daughter's car and she took it to a technician so I wasn't there when he diagnosed these two problems.

The compressor works and can be jumped but I believe it was not kicking in when he tried to test it. He diagnosed the reason was the pressure switch.

I have access to a used one from a system with some charge so we'll try that cheap fix first. Appreciate the advice about not losing the charge.

[Legacy777]

You're welcome.  Let us know how things go and if the temp switch works.