Test E: The Electronic Automatic Temperature Control (EATC) Module Does Not Respond To The Diagnostic Tool
PINPOINT TEST E: THE ELECTRONIC AUTOMATIC TEMPERATURE CONTROL (EATC) MODULE DOES NOT RESPOND TO THE DIAGNOSTIC TOOLE1-E3:
Normal Operation
The EATC module communicates with the diagnostic tool through the medium speed controller area network (CAN), circuits 2180 (WH/BK) and 2181 (BK/YE). Check circuits 2180 (WH/BK) and 2181 (BK/YE) between the EATC C228b and the data link connector (DLC) C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in one of the medium speed CAN circuits, damage to the DLC C251, damage to the EATC C228b, or a problem in an in-line connector.
Possible Causes
- medium speed CAN circuit 2180 (WH/BK) open
- medium speed CAN circuit 2181 (BK/YE) open
- EATC module
- EATC module C228b