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Test E: The Electronic Automatic Temperature Control (EATC) Module Does Not Respond To The Scan Tool

PINPOINT TEST E: THE ELECTRONIC AUTOMATIC TEMPERATURE CONTROL (EATC) MODULE DOES NOT RESPOND TO THE SCAN TOOL

Normal Operation
The EATC module (if equipped) communicates with the scan tool through the standard corporate protocol (SCP) communication network. Circuits 914 (TN/OG) (SCP +) and 915 (PK/LB) (SCP-) provide the network connection to the EATC module. The EATC module shares the SCP network with the lighting control module (LCM), the driver door module (DDM) (if equipped), the overhead console module (if equipped) and the instrument cluster. Voltage for the EATC module is provided by circuits 1812 (BN/WH) and 1566 (RD/YE). Circuit 57 (BK) provides ground.

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- EATC module


E1:






E2-E3:






E4: