2001 Prius - A/C light blinks

[osiris12]

Just today with the temps here in northeast USA topped 100F, I noticed my ac in my 2001 went off. Actually the little square light started blinking and I noticed no cold air was coming out. I was climbing a steep hill.

So I shut down the ac. After I crested the hill I turned the ac on again, and it kept on working for over 50 miles to my destination.

I'm not sure what that was, but the car was under a lot of strain trying to climb a hill in 100+ temps. Guess the computer decided to start shutting systems down?

Has anyone expreinced this before on their 1st gen Prii?

[Patrick Wong]

This makes sense; I am surprised that the turtle light did not come on.

[ChapmanF]

Originally Posted by osiris12

I noticed my ac in my 2001 went off. Actually the little square light started blinking

The green light within the A/C button? If I recall correctly, the manual says that light will blink if the A/C compressor isn't spinning at the speed the ECU expects. The ECU knows the engine RPM and the compressor RPM (there's a sensor), and the two speeds should be what you'd expect from the relative pulley sizes. If the compressor RPMs are lower than that, the ECU decides the belt (or magnetic clutch?) is slipping, and blinks the light.

I think the ECU also does normally disengage the A/C when you're asking for strong acceleration, but I haven't noticed it blinking the light for that. You might want to check the belt tension.

You can get the diagnostic code out of the A/C ECU without any special tools. IIRC the dance is: IG ON (with fan switch set to off), push A/C 3 times, turn fan switch to auto. Then count the blinks of the lights. Steady fast blinking means no diagnostics. Otherwise you get a 2 digit code like "blink blink blink (pause) blink blink" for 32. There can be more than one code, and the whole sequence will repeat in case you don't copy one down the first time (which means you know you've seen the whole sequence as soon as you see the first code repeated).

-Chap

p.s. one of the diagnostic codes is for the solar sensor, and you will always get that one if you activate the diagnostic mode when it's dark out. Don't pay it any mind unless you also get it in sunlight.

[nikfish]

My best guess is it was too much for the AC to handle, so it shut off. Our AC compressor in a 2001 slowly died. It started with blinking once in a while on really hot days... shut off the AC, turn it back on two minutes later and it was fine.

Then it became more frequent. Now it will even occasionally happen in the winter with the defog on.

[ChapmanF]

Originally Posted by nikfish

Our AC compressor in a 2001 slowly died. It started with blinking once in a while on really hot days... shut off the AC, turn it back on two minutes later and it was fine.

Then it became more frequent. Now it will even occasionally happen in the winter with the defog on.

Hi Nikfish,

Are you saying you still have the 2001 and this still happens?

Why not read off the trouble codes (can be done without any special tool, see above for how) and post them here?

There's a variety of possible explanations other than "compressor died." Some could be easy to fix.

-Chap

[osiris12]

Wow, thanks for the great feedback. I will check the codes Chap.

Except for this, my 2001 is going strong. I'm going to keep it until the new models come out. I already have a 2006 which is a great car too.

[statultra]

when the a/c light blinks the a/c compressor shut off for some reason, for me this happened when my a/c compressor seized due to a tiny oil leak from a crash. This also happens if the clutch does not engage for the a/c compressor. This could be for a variety of reasons, the magnetic thing doesnt pull the clutch in, or the line pressure is low.

i would suggest u turn on the car and turn on the a/c and listen to the compressor as it "clicks" on if it sounds loud or grinding kinda, its due to the lack of refrigerant oil