Blinking A/C light usually means it needs servicing. Most likely, you'll need a refill so take it in to get looked at.

 

Yeah I'm with ^

A blinking A/C light means an issue with the A/C system.

 

Freon is low if the a/c light is flashing

 

Took it in, they said the freon was about 1/2 empty, so the evaced it, put in dye, and filled it to spec. It still flashes after a bit, not as bad/often, and it will blow cold air, after blinking, but does it over again. Like I said not as bad, I could probably live with it, that was $171.00, he said for another 90-200 dollars, they could narrow it down and find the problem, they have it narrowed to a electrical problem.

 

What Toyotas have the flashing A/C light function? When did they start using it? My Cressida's just stays lit when the A/C runs low.

 

My 1985 Camry did it.

the 01-03 prius have the built in diagnostics system for a/c. To activate it (assume the blower are in off position initially), turn the ignition switch from off to on (without start the vehicle). press the a/c swith 3 times and turn the blower switch from off to auto.

Note: perform all those steps above within 5 sec or else it won't work.

When the step perform correctly, the system will light up the a/c light, defogger light, "max" light and the recirculate light 4 times to perform indicator check. Note: check that all the indicators light up and go off at 1 second intervals 4 times in succession.

After the indicator check is ended, the system begin the diagnostics automatically.

If there is no error code stored in, the light will have a steady fast blink.

If there is a code stored in the system, count the blinking to figure the code.
Example 1: blink blink(pause) blink blink blink equal to code 23 which is abnormal refrigerant pressure.

Example 2: blink(pause) blink blink equal to code 12 which is ambient temp sensor problem.

If there is multiple code stored in the system, lower number (code) will ouput first.

example: blink(pause) blink blink (long pause) blink blink(pause) blink blink blink equal to code 12 and 23.

Try to get the code and I will decode from the diagnostic trouble code chart for you.

Wow, the system is more advanced than I thought it was. In older Toyotas the light just flashed if there was a problem. e.g. the pressure was low due to a leak or lack of freon.

 

the 01-03 prius have the built in diagnostics system for a/c. To activate it (assume the blower are in off position initially), turn the ignition switch from off to on (without start the vehicle). press the a/c swith 3 times and turn the blower switch from off to auto.

Note: perform all those steps above within 5 sec or else it won't work.

When the step perform correctly, the system will light up the a/c light, defogger light, "max" light and the recirculate light 4 times to perform indicator check. Note: check that all the indicators light up and go off at 1 second intervals 4 times in succession.

After the indicator check is ended, the system begin the diagnostics automatically.

If there is no error code stored in, the light will have a steady fast blink.

If there is a code stored in the system, count the blinking to figure the code.
Example 1: blink blink(pause) blink blink blink equal to code 23 which is abnormal refrigerant pressure.

Example 2: blink(pause) blink blink equal to code 12 which is ambient temp sensor problem.

If there is multiple code stored in the system, lower number (code) will ouput first.

example: blink(pause) blink blink (long pause) blink blink(pause) blink blink blink equal to code 12 and 23.

Try to get the code and I will decode from the diagnostic trouble code chart for you.

 

the 01-03 prius have the built in diagnostics system for a/c. To activate it (assume the blower are in off position initially), turn the ignition switch from off to on (without start the vehicle). press the a/c swith 3 times and turn the blower switch from off to auto.

Note: perform all those steps above within 5 sec or else it won't work.

When the step perform correctly, the system will light up the a/c light, defogger light, "max" light and the recirculate light 4 times to perform indicator check. Note: check that all the indicators light up and go off at 1 second intervals 4 times in succession.

After the indicator check is ended, the system begin the diagnostics automatically.

If there is no error code stored in, the light will have a steady fast blink.

If there is a code stored in the system, count the blinking to figure the code.
Example 1: blink blink(pause) blink blink blink equal to code 23 which is abnormal refrigerant pressure.

Example 2: blink(pause) blink blink equal to code 12 which is ambient temp sensor problem.

If there is multiple code stored in the system, lower number (code) will ouput first.

example: blink(pause) blink blink (long pause) blink blink(pause) blink blink blink equal to code 12 and 23.

Try to get the code and I will decode from the diagnostic trouble code chart for you.

Thanks, sorry for the late post, This afternoon, I will do this, and get back with you. Thanks again, wanted to say, when it it cooler outside, it works longer.

 

You wrote:

Try to get the code and I will decode from the diagnostic trouble code chart for you.[/quote]

My '03 Sweetie (99k) is warm and blinking. You're code retrieval worked like a charm. What does your A/C ECU DTC chart say for a code 21 (blink, blink, short pause, blink)?


Just replaced the Blower Motor for the a/c and heat inside cabin controlled. Let me know if anyone needs guidance. Total Cost $45 + 2 hrs of my time.

 

Code 21 is open or shot in solar sensor circuit. Possible trouble area are:
1. solar sensor
2. Harness or connector between room temperature sensor (locate underneath the shift lever, behind the small vent) and a/c amplifier, or
3. A/C amplifier.

note that if you are checking your dtc code during night time or area without sunlight shine directly to the solar sensor, the code 21 will come out as well.

 

went out and did the test, came up on a code 21, 2001 prius. Thanks

 

Hey i would like to know if you fixed the problem with your 2001 prius?
I have 2002 prius and i have the same problem and i got the code 21.
let me know please.

 

Hi all,
New to this forum business and new to posting. Last summer my 2003 Highlander cools to 10 degrees celsius. Toyota dealer couldn't find leak so he purged and refilled and all was cool. (pun not intended). This year it's 10 degrees again. Toyota dealer charges $103 to diagnose then offers to sell me a clutch relay for $82, no wait - that was 2 weeks ago ago - now its up to $122 this week. Parts Source sold me one for $81 - no change to cooling. On a trip to US A/C light starts flashing and A/C not working. I switch the horn relay for the clutch relay. We're back to 10 degress.

I'd like to try the A/C diagnostic system. Where can I get a complete step by step and list of codes?
Thank you for your help.
TK.

 

On a trip to US A/C light starts flashing and A/C not working. I switch the horn relay for the clutch relay. We're back to 10 degress.
QUOTE]


Is this in the fuse box, like the drivers side? thanks

 

The a/c light blinking on any toyota vehicle for the most part is related to a/c compressor rpm sensor.
It compares engine rpm to a/c compressor rpm. (belt loose or magnetic clutch failure)
On the prius vehicles it's the a/c clutch worn out. If you look around the a/c compressor, one will notice a brown dust (like something is rusting up, and coming apart), thats a/c clutch material.
I've done a few on prius this year alone.
Hope this helps....... JM

 

The a/c light blinking on any toyota vehicle for the most part is related to a/c compressor rpm sensor.
It compares engine rpm to a/c compressor rpm. (belt loose or magnetic clutch failure)
On the prius vehicles it's the a/c clutch worn out. If you look around the a/c compressor, one will notice a brown dust (like something is rusting up, and coming apart), thats a/c clutch material.
I've done a few on prius this year alone.
Hope this helps....... JM

Do you get the part from toyota, or elsewhere?