Hi, I have a Nissan Altima 2000 with 93000 miles. My air conditioner is acting strange. Sometimes it works and sometimes it doesn’t. I get the air con serviced yearly and take good care of the car in general. Last summer I was told they couldn’t find anything wrong with the air con. It also seems like it doesn’t work on the hottest days and works fine on the coolest! Any ideas? If so, how much do you think it will cost me? I live in Chicago, IL.
When was the last time you changed the accessory belt on the car?
One that has been on for a long time might be stretched out, and not getting all the power into the compressor motor under high demand situations.
Other than that, make sure the cooling system is full of coolant (this can be tricky on Altima’s, because they can get air in the system that requires a special procedure to bleed out), and that the radiator fans are turning on when you activate the a/c, and that there aren’t any bugs (or damage, for that matter) in the fins of the radiators.
The only other thing is to check the charge on the a/c unit, and though you can buy stuff from local auto parts stores that can do this, if you aren’t good with working on your car, you should leave this to the professionals.
Thanks for the great info! I’ll take a look at all of the things you mentioned.
How does the A/C depend on coolant level? Is it because it needs the fans, which need the coolant full to run?
I think it’s more likely an electrical problem, like the pressure switch on the dryer canister, or the clutch relay near the fuse box. Perhaps even the dash switch is worn on a car this age.