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

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

I1:

I1-I2:

I3-I4:

Normal Operation
The EATC module communicates with the scan tool through the medium speed controller area network (MS-CAN). Circuits VDB06 (GY/OG) (MS-CAN +) and VDB07 (VT/OG) (MS-CAN -) provide the network connection to the EATC module. The EATC module is only on vehicles equipped with automatic climate control. The EATC module shares the MS-CAN network with the smart junction box (SJB), the instrument cluster, the audio unit, the THX(R) amplifier (if equipped), the satellite radio receiver (if equipped), the driver seat module (DSM) (if equipped), the driver door module (DDM) (if equipped) and the climate controlled seat module (if equipped). Voltage for the EATC module is provided by circuits CBP20 (YE/VT) and SBP07 (WH/RD). Circuit GD116 (BK/VT) provides ground.

Possible Causes
- Fuse
- Circuit CBP20 (YE/VT) open
- Circuit GD116 (BK/VT) open
- Circuit SBP07 (WH/RD) open
- Circuit VDB06 (GY/OG) open (MS-CAN +)
- Circuit VDB07 (VT/OG) open (MS-CAN -)
- EATC module