STARTING THE Cool Down TEST - MTC SYSTEM

Once all of the prerequisites have been met, the Cool Down Test for the MTC system can be actuated by performing the following:

Fig 1: Identifying Blower Motor Control & A/C Mode Switch

Courtesy of CHRYSLER LLC

1. Verify that the ignition is in OFF.
2. Turn the blower motor control (1) to OFF.
3. Start the engine.
4. Press and hold the A/C mode switch (2) down and then turn the blower motor control to high speed. Continue to hold the A/C mode switch down until the A/C status indicator begins flashing, Then, release the mode switch.

Once actuated, the MTC A/C-heater control automatically positions the air-doors for optimal A/C performance and sends a request for A/C operation to the cluster (CCN) via hardwired circuits. The Cool Down Test can take up to two minutes to run. The test will stop running if any of the following occurs:

• The ignition is turned to any position other than RUN.
• The blower motor control is turned to the any position other than high speed.
• DTC 83 or 84 sets during the Cool Down Test.

While the Cool Down Test is running, the A/C status indicator will flash. During this time the A/C-heater control will ignore most of its inputs. If the MTC system passes the test, the A/C status indicator will stop flashing. However, if the MTC system fails the test, both the A/C and EBL status indicators will flash alternately and an active DTC 35 will set. The status indicators will continue to flash until either a successful Cool Down Test is executed or until the vehicle's ignition on time has exceeded a specified value. In addition, DTC 35 will remain active until a successful Cool Down Test is executed. Always check for and diagnose DTCs present in the A/C-heater control after running the Cool Down Test. If the Cool Down Test fails, service the heating-A/C system as required.