Diagnostic System Check - Retained Accessory Power

A Diagnostic System Check - Retained Accessory Power:

TEST DESCRIPTION
The number(s) refer to the step number(s) on the diagnostic table.
2. Lack of communication may be due to a partial malfunction of the Class 2 serial data circuit. The specified procedure will determine the particular condition. Attempt to communicate with the following modules:
^ Cellular Telephone Module
^ Dash Integration Module (DIM)
^ LH Front Door Module
^ LH Front Power Window Switch
^ LH Rear Door Module
^ Memory Seat Module (MSM)
^ Navigation Data Processor
^ Navigation Display Module
^ Radio (W/UY4)
^ Radio (W/O UY4) Radio Amplifier (W/U57) Radio Amplifier (W/O U57)
^ Rear Integration Module (RIM)
^ RH Front Door Module
^ RH Rear Door Module Steering Column Module
3. The Symptom Table will determine the correct diagnostic procedure to use.
4. The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.
7. If DTC B1422 is set, the RAP feature may be disable.

For a description of the RPO Code(s) shown in this article/image, refer to the RPO Code List found at Vehicle/Application ID Application and ID