donwanjrboy

2012 chevy tahoe...85 degrees outside and the a/c button blinks 3 times and nothing

Schutrum

Prob low on Freon

in2pro

https://chevroletforum.com/forum/tah...-blinks-35282/


#07-01-38-003: Information for Vehicles with HVAC Control Module A/C and Recirculation Indicators Flashing


Subject: Information for Vehicles with HVAC Control Module A/C And Recirculation Indicators Flashing


Models: 2008 Buick Enclave

2007-2008 Cadillac Escalade Models

2006-2007 Chevrolet Monte Carlo

2006-2008 Chevrolet Impala

2007-2008 Chevrolet Avalanche, Equinox, Silverado, Suburban, Tahoe

2007-2008 GMC Acadia, Sierra, Yukon Models

2007-2008 Pontiac Torrent

2008 HUMMER H2

2007-2008 Saturn OUTLOOK

2008 Saturn VUE




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Condition/Concern
Some customers may comment that the Air Conditioning (A/C) indicator on the Heating Ventilation and Air Conditioning (HVAC) Control Module flashes then turns off after they press the A/C button. Others may comment that the Recirculation indicator on the HVAC Control Module flashes then turns off after they press the Recirculation button.

This is normal operation for the HVAC Control Module and indicates that the A/C or Recirculation function is not available at this time.

Reasons that the A/C may not be available (calibrated values vary by program) are listed below. Consult the appropriate vehicle Service Information (SI) for detailed HVAC Description and Operation:

• Ambient Air Temperature is too low (if equipped with Ambient Air Temperature Sensor)

• Vehicle voltage less than 9.5 volts

• Refrigerant Pressure too low

• Refrigerant Pressure too high

• Engine Coolant Temperature too high

• Engine is not in RUN

• HVAC Control Head is in the OFF position

Reasons Recirculation may not be available: Mode switch in Floor, Defog or Defrost mode.

The reason(s) A/C is currently disabled can be viewed with a Tech 2® by navigating to HVAC Data display and viewing the "A/C Permission" parameter.

Recommendation/Instructions
Do not replace the HVAC Control Module for a flashing A/C Indicator or flashing Recirculation Indicator, as this is normal operation.

Cusser

When similar happened on our 2005 Yukon (hot air coming out) it was due to a malfunctioning actuator under the dash. New Dorman unit fixed that.

LoneMech

Please learn from my mistakes and check your belt first lol. I tried everything just to look and see my belt hanging from the tensioner.

Cusser

Great. But when my AC belt on my 2005 kept breaking, it was due to "compressor slugging" and I had to replace my compressor to fix.

Following are general AC system things to check when a vehicle has no AC:
1. Start engine, turn on AC, and see if the compressor drive plate (the center of the compressor) is turning at same speed as the belt and compressor pulley.2. Engine off, put a wrench on the center of the AC compressor drive plate, and see if you can rotate the compressor clockwise. There should be a little resistance, but should not be locked up. If compressor is locked up, you're looking at minimum) of new compressor, new condenser, new drier, back-flushing out the AC lines from the drier to the compressor with solvent.

3. If compressor is not locked up, maybe the refrigerant has leaked out enough where there is insufficient pressure to activate the pressure switch to "close" the circuit to the AC compressor. Read the low side and high side pressures, post those.

4. Whatever you do, do NOT add any sealer or refrigerant containing sealer. And do not blindly add refrigerant, "thinking" that it's low.

5. I suggest an AC specialty shop or an independent local ASE-certified mechanic for any repairs, not a dealer.