Blinking AC light

[EDunford]

Question for everyone.
2006 2500 SLT 4x4.
My AC will be working great then the light goes on and off (along with the compressor) and the airbag indicator comes on at the same time, it will do this for roughly 5-10min and then will start working normal again. Could this be the TIPM?

Thanks for the help

 

[Ozymandias]

Found this:

‐‐------‐------------

Good afternoon, when ever the a/c light is blinking...it means the system ran a test and the results came back...failed.If the vehicle is equipped with electric heated glass, this light will flash as well. The test that failed is most likely the a/c cool down test.



The entire system needs to be up to normal operation standards such as correct freon level for example. You can manually cause the system to rerun the cool down test and then see if the results are different.





Here is the info for the test: (in order to run the test....you will need a scanner that is capable of accessing the HVAC control module...not just your basic code reader or scanner...thats what they mean when you read below and they mention DRB III. The DRB III is the factory scanner that the dealership uses)



A/C STATUS INDICATOR FLASHING





Theory of Operation
Running the AC Cool down test will cause the A/C status indicator to flash. If the test fails, the status indicator will continue to flash until either the test returns passed or the ignition key is cycled. When the A/C status indicator is flashing, it will not indicate A/C operating status. However, the A/C mode switch will continue to function normally. For vehicles equipped with EBL, when the A/C status indicator is flashing, the EBL status indicator will not function. However, the EBL mode switch will continue to function normally.


Possible Causes
A/C COOLDOWN TEST FAILED

1. PERFORM THE A/C COOLDOWN TEST




NOTE: The following are prerequisites of the Cool down Test. Verify each of the following before running the test:

• Verify that no Evaporator Temperature Sensor related DTCs are not active. If active, diagnose and repair the DTC before proceeding. Refer to the Table of Contents in this Section for a complete list of HVAC related symptoms.
• Verify that the refrigerant system has an adequate charge. Check and repair as necessary before proceeding
• Verify that the blower motor operates correctly in all speeds. Diagnose and repair all blower related faults before proceeding.
• Verify that the work area ambient temperature is above 21.1°C (70°F) before proceeding. Move the vehicle to a warmer work area if necessary.
• Verify that the evaporator temperature is above 12.7°C (55°F) before proceeding.
• Verify that the Mode Select control is set to the panel position.
• Verify that the A/C compressor is not running. If the compressor is running, turn the A/C off and allow the evaporator to warm up before proceeding.

Start the engine.
Turn the Blower control to the high speed position.
With the DRBIII® in HVAC, select System Tests and then select AC Cool down test. Allow one minute for the test to complete. One or more status messages will display on the DRBIII® after running the AC Cool down Test. These messages will clear after paging back out of this test function. Therefore, it is important to note all messages before doing so.

Does the DRBIII® display a status message that indicates a fault has occurred?

Yes, Blower Not On High

• Diagnose and repair the fault. Refer to Blower Not On High in this section for the diagnostic test procedure.

Yes, Cool down Test Sensor Failure

• Diagnose and repair the fault. Refer to Cool down Test Sensor Failure in this section for the diagnostic test procedure.

Yes, Cool down Time Excessive Fault

• Diagnose and repair the fault. Refer to Cool down Time Excessive Fault in this section for the diagnostic test procedure.

Yes, Cool down Test Too Cold To Start

• Diagnose and repair the fault. Refer to Cool down Test Too Cold To Start in this section for the diagnostic test procedure.

No

• Test Complete
• Perform BODY VERIFICATION TEST - VER 1.

At this point there is no one item you can check with out the proper equipment, otherwise you would be just guessing and mostly likely guessing wrong.

 

[Ozymandias]

Means you need decent Diagnostic performed before you start throwing parts at it that can easily ruin you.

 

[EDunford]

Awesome.
Thank you