Diagnostic Procedure
*FRONT BLOWER RUNS AT ONLY ONE SPEED - DIAGNOSTIC PROCEDURE
| TEST | ACTION | APPLICABILITY |
|---|---|---|
| 1 | With the DRBIII®, read PCM DTCs. Are any HVAC related DTCs present?
|
All |
| 2 |
NOTE:
Active DTCs must be resolved before diagnosing stored DTCs.
NOTE:
Anytime a DTC becomes active or a Cooldown Test fault message is displayed proceed to the conclusion question.
NOTE:
If multiple DTCs appear, diagnose those that relate to a short circuit first. Start the engine.Press the ATC's PWR switch on.Verify that the front blower motor operates correctly in all speeds.Diagnose and repair all blower related faults before proceeding with this test.
CAUTION:
The work area ambient temperature must be above 15.6°C (60°F) and the evaporator temperature must be above 12°C (53°F) in order to test A/C system operation.
NOTE:
Before actuating the AC Cooldown Test, 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 with the test.
NOTE:
Running the AC Cooldown test will cause the DELAY & Snowflake VF segments to flash. If the test fails, the DELAY & Snowflake VF segments will continue to flash until the vehicle is driven more than 3 miles or a successful Cooldown test is performed.
NOTE:
Messages will display on the DRBIII® after running the AC Cooldown Test. These messages will clear after paging back out of this test function. Therefore, it is important to note all messages before doing so. With the DRBIII® in ATC, System Tests, actuate the AC Cooldown test. If any Cooldown Test fault messages appear, proceed to the conclusion question, otherwise, proceed as follows:Set the front blower speed to low.Press the REAR fan mode switch on, so that it is in manual mode. The word "REAR" should display on the ATC display panel. The word "AUTO" should not be displayed. Press the DUAL mode switch off. The word "DUAL" should not be displayed on the ATC display panel. This will allow the DRIVER BLEND mode switch to control both driver and pass temp settings.Set the driver temperature to 60°F (16°C). The passenger temperature should also display 60°F (16°C).Monitor the DRBIII® for active ATC DTCs while performing the following test steps.Press the RECIRC mode switch on, wait 30 seconds, and then press it off.Press the A/C mode switch on, wait 30 seconds, and then press it off.Press the REAR DEFOG mode switch on, wait 30 seconds, and then press it off.Press the EBL mode switch on, wait 30 seconds, and then press it off.Press the DUAL mode switch on.Set the driver temperature to the max heat setting, wait 30 seconds, and then set it to the max cool setting. Repeat this step for the passenger temperature.Press the MODE switch, placing the mode door in each position for 30 seconds, and then return it to the panel position.Press the AUTO HI mode switch, wait 30 seconds, and then press the AUTO LO mode switch. When the function is complete, reset the front blower speed to low.Turn the Rear Booster Fan Rear Control switch to AUTO for 30 seconds, then slowly turn it from AUTO to high speed and then back to AUTO.With the DRBIII® in ATC, Miscellaneous, reset the ATC.Does the DRBIII® display any active ATC DTCs or Cooldown Test fault messages?
|
All |
| 3 | With the DRBIII®, read PCM DTCs. Are any HVAC related DTCs present?
|
All |