A/C suddenly not working

When was the last time you used the AC.

Yes, it is possible that while replacing the timing belt they may have disconnected one of the hoses, but it's unlikely. Since the car is a '97, it would seem the AC would come on with the defroster, and this does two things: it dries the air to the windsheild, making defogging more efficient, and it keeps the freon and oil circulating and keeping the seals fresh.

You could 'test' the system by pushing the Scraeder valve and see if any gas escapes, or take it to an AC shop you trust and have them measure the amount of gas in the system.

Not sure exactly, but probably sometime in March, before I had the timing belt replaced. As I said, I use it during the winter to defog the windows. I live in the San Francisco area, so winter = rain and fogged-up windows, not icy temps.

It doesn't come on automatically, no. I have to push the A/C button explicitly.

Thanks, I'll get this checked out.

Does the AC pulley turn when you turn it on? Does the coil wire show battery voltage? Only then do you do a pressure test, but very carefully better get a knowledgeable friend.

hachi is right, for decades most ACs just swing out of the way if even need to be touched. So don't jump on the mechanic just yet. It's possible that a wire was knocked loose (often after work). So check those even before going into pressure.

For reference, check FAQs on the AC site:

There are several things you can check yourself if you know what the A/C components look like.

If you are not familiar with the compressor and receiver/drier, go to

click on the vehicle repair guides link, and look up your car. The AC repair info is in the chassis electrical section.

First, see if the accessory drive belt is installed on the AC compressor pulley and that the plug for the wire for the compressor is plugged in. When you engage the AC system, the clutch on the compressor pulley should engage and the drive belt should turn the compressor.

If that stuff is OK, turn on the AC, set the temp to full cold, fan on full high, and look at the sight glass in the receiver/drier. It should look like clear water flowing past the glass. If you see foam or nothing at all, the system needs charging. If the system is really low on refrigerant, the low pressure safety switch will prevent the AC clutch from engaging to prevent damage to the compressor.

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Thank you for this very useful information. I'm a typical consumer who knows only a few things about auto mechanics. Air conditioning is not included. This is the first car I've owned that's even had it, and it hasn't broken down before now. So even the terminology is brand new to me.

Thanks!

That's how I learned best. I had some car trouble that I apparently caused but I took it to about 3-4 independent shops and the dealer and nobody could figure out what was wrong. Plenty of misdiagnoses, a couple parts repaired that I do not believe were the problem, and then even the GM of the dealership said maybe I should trade it in -- this on a car with less than 100k on the odometer and was owned less than a year at that point.

Ended up being the dealer found a dirty/cracked injector. It took more than 3-4 shops and the dealer two or three visits to FINALLY figure that out. Trust me -- I did a lot of research on my own and even had suggested the injectors only to be told that wasn't likely. They refused to check a lot of things I suggested -- even though -- get this -- even though it was OBVIOUS not much of their analysis did anything. Not even the 'Master Technician' seemed to be able to figure mine out.

After they replaced that faulty injector, bam no problems. However, due to this incident I learned a lot about how a car runs from this group, a Haynes manual, and lots of reading. Honestly, had I not done reading and realized I had a fixable problem, I might have been inclined to give up. It's not like I am or was made of money and most had me convinced this problem was just straight un-fixable and I didn't have the money to keep taking it to shops only to get told 'we can't find the problem.'

Good luck!

You're welcome! Stick around here and you'll learn a little about Toyotas if you're willing to wade through all the OT stuff.

I believe on that car, replacement of the timing belt requires swinging the A/C compressor out of the way, and if the hoses were twisted quite a bit in the process, their fittings could have leaked. It's highly unlikely the garage didn't cause the failure.

Just checking - are you saying it's highly *unlikely* that they caused the failure, or highly *likely* they caused it? Double negatives always cause trouble. :)

Thanks.

It is nice that your story had a happy ending. In the 'old days' - maybe even up to the mid 90's - many or most performance problems could be solved with a conventional tune up. Unfortunately, with today's complex cars too often a 'performance problem' (ie. ignition, fuel, emissions) truly can't be fixed. The flat rate system at most shops works against a thoughtful diagnosis - and customers will often rebel against 2 -3 hours of tech time just to find a problem plus the often expensive cost of todays parts. Fortunately, w/today's cars those systems are pretty reliable - but may the gods of autmobiles take pity on anyone who does find their car with a 'performance' problem!

It is nice that your story had a happy ending. In the 'old days' - maybe even up to the mid 90's - many or most performance problems could be solved with a conventional tune up. Unfortunately, with today's complex cars too often a 'performance problem' (ie. ignition, fuel, emissions) truly can't be fixed. The flat rate system at most shops works against a thoughtful diagnosis - and customers will often rebel against 2 -3 hours of tech time just to find a problem plus the often expensive cost of todays parts. Fortunately, w/today's cars those systems are pretty reliable - but may the gods of autmobiles take pity on anyone who does find their car with a 'performance' problem!

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Fortunately, engines still need the same 3 things to run as they did 30 years ago - air, fuel, and a source of ignition, and Ohm's law has not changed. Keeping those two basic thoughts in mind when diagnosing a problem works wonders, even in a modern vehicle.

Sorry. It's highly likely the garage caused the failure.