Control Module HVAC: Testing and Inspection

EMTC Module - Diagnostic Methods
The EMTC module must be diagnosed by first retrieving any DTCs, if present.

- On-demand (hard fault) DTC indicates that the fault is currently present. An on-demand DTC suggest a wiring fault, disconnected connector or component failure.
- A continuous (intermittent) DTC alone (corresponding on-demand DTC is not present) indicates that the fault is an intermittent condition and may not be currently present. A continuous only DTC suggests a poor wiring connection, loose pin or terminal or intermittent component failure.

On-demand (hard fault) or continuous (intermittent fault) DTCs can be retrieved using a scan tool. If using a scan tool, refer to the scan tool operating manual.

If no DTCs are present, see SYMPTOM TROUBLESHOOTING CHART - CLIMATE CONTROL Symptom Related Diagnostic Procedures for the appropriate diagnostic action.

EMTC Module - Cold Boot Process
The purpose of the cold boot process is to allow the EMTC module to reinitialize and calibrate the actuators. To carry out the cold boot process, follow the steps below.
- Turn the ignition switch to the OFF position.
- Disconnect the EMTC module electrical connectors.
- Wait one minute.
- Connect the EMTC module electrical connectors.
- Turn the ignition switch to the ON position.
- Select any position except OFF on the EMTC module.

The EMTC module will now initialize and calibrate the actuators. Calibration of the actuators will take approximately 30 seconds.