I bought my 90SE in November and I have not used the A/C yet here in Indiana. However I can see that day rapidly approaching. I have never had a car with A/C (that worked lol). So I want it on my Max.

the previous owner told me that the A/C needed a recharge (I just assumed that it did, and that the compr. is probably shot too).

In other cars I have driven, when I press the AC button, the engine RPMs change slightly due to the load from the compressor. In my max this does not happen when I turn it on. Is that a sign that my compressor is bad?

I might just go buy a recharge bottle for it and see if it gets any cold coming out of there. I would like to know if my comp. is bad so I can start saving my pennies and watching Ebay for one.. Any thoughts?

 

AC is also good to use sometimes in winter for getting condensation off cabin.

Compressor does not come on? You can hear the compressor free-clutch to engage if u open the hood, as smbdy puts AC on. If it does not, ctrl is amiss. (bad ctrl board or ECU?) Feel for the cooling hose, working AC has a long tube trying to get Indiana colder... btw. insulate it.
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Edit: The compressor itself has one wire going in: as all ctrl requirements are met, AC relay connects +12V here. Relay coil +12v is fed by igns sw via 10A fuse20; ground is ECU controlled. Hot wire to compressor comes via this relay, comes from ign sw via 10A fuse10.

You may test compressor and its clutch by jumping +12V to that connector, it should engage.

 

if the idle doesn't change then either:
a. compressor is unplugged
b. it needs a recharge, so the compressor isn't kicking on

 

I say b.

Remember, if the system sensing the freon is low, the compressor won't engage. As the freon also lubes the compressor bearings etc.. So this prevents the compressor from being ruined.

It's probably low on freon. But there is probably a leak. ie.. the reason why it's low on freon

 

I wouldn't know.
both my last 2 maxs had their A/c working fine.
though my 84 was running on 8ozs when we junked it.
A/C still worked good though

 

If you want to force-test the AC, the connector on the driver side just above the condencer can be shorted to simulate 'enough pressure' condition.
By the way, do you have auto climate control? Does it show correct ambient temperature? If it always shows lowest possible reading (-32°C in my car) than the ambient temp sensor is dead or disconnected. That way the AAC control module will always think it's winter. The sensor is just behind the top of the bumper on the post in front of the AC radiator (below the hood latch).

 

No auto-control. I didn't realize that is sensed that is is low, that would explain it, hehe.. I will buy a bottle of the new stuff and fill her up. That would be sweet if that is all it needs, I will let the board know. Thanks!

Brian

 

Test shorting the pressure sensor harness first. The AC clutch should kick in. What if it does not?

 

A/C compressor does not care where/which car the +12V comes from: jumping to AC is easy valid way to tst. Switches/wirings only multiply error possibilities in compressor tst.

 

If he's system is full and he does have a dead pressure sensor the top up is useless. But you are right, that is not the most reliable way to test the clutch. Just one of the many tests to run before going for a top up.