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

E1-E2:

E2-E3:

E4:

Normal Operation
The EATC module 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 is also tied to the UBP network. The EATC shares the SCP network with the smart junction box (SJB), the speed control actuator and the instrument cluster. Voltage for the EATC module is provided by circuits 1001 (WH/YE) and 1003 (GY/YE). Circuit 1203 (BK/LB) provides ground.

Possible Causes
- Fuse
- Circuit 914 (TN/OG) open (SCP +)
- Circuit 915 (PK/LB) open (SCP -)
- Circuit 1001 (WH/YE) open
- Circuit 1003 (GY/YE) open
- Circuit 1203 (BK/LB) open
- EATC module