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Control Assembly: Description and Operation

Climate Control Assembly (DATC Module)
The Dual Automatic Temperature Control (DATC) module:
- is located in the instrument panel.
- has a vacuum fluorescent display for displaying set temperature, ambient temperature, function and Diagnostic Trouble Codes (DTCs).
- utilizes an On-Board Diagnostic (OBD) feature to supply the technician with diagnostic trouble codes (DTCs). These DTCs direct the technician to the inoperative component.

Rear Audio/Climate Control Module
The rear audio/climate control module is equipped on limousine (long wheel base) vehicles. The rear audio/climate control module converts an input from the rear audio/climate control switch, then signals the Audio Control Module (ACM) via the Audio Corporate Protocol (ACP) bus. The ACM then signals the DATC module over the J1850 communications network (Standard Corporate Protocol [SCP] bus).

Steering Wheel Audio/Climate Control Switch
The steering wheel audio/climate control switch, located on the right side of the steering wheel, allows the driver to adjust the passenger compartment temperature setting and manually override the blower motor speed setting. For removal and installation of the steering wheel audio/climate control switch, refer to Radio, Stereo, and Compact Disc.