Electronic Automatic Temperature Control (EATC) and Dual Automatic Temperature Control (DATC) Module - Diagnostic Methods: Notes
The electronic automatic temperature control (EATC) and dual automatic temperature control (DATC) system must be diagnosed by first retrieving any DTCs, if present.
- An on-demand (hard fault) DTC indicates that the fault is currently present. An on-demand DTC suggests 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.
On-demand DTCs can also be retrieved by carrying out the EATC AND DATC MODULE ON-DEMAND SELF TEST . To retrieve and/or clear continuous DTCs, carry out the DATC/EATC MODULE - RETRIEVE CONTINUOUS DTCS procedure. Always carry out the EATC AND DATC MODULE ON-DEMAND SELF TEST before retrieving continuous DTCs.
If no DTCs are present, GO to SYMPTOM CHART for the appropriate diagnostic action.