Diagnostic System Check

Install scan tool. If scan tool powers up, go to next step. If scan tool does not power up, perform appropriate diagnostic procedure. See SELF-DIAGNOSTIC SYSTEM in appropriate BODY CONTROL MODULES article.
Turn ignition switch to ON position. Following scan tool manufacturer's instructions, attempt to establish communication with Driver Door Module (DDM) and Powertrain Control Module (PCM). If communication with DDM and PCM is established, go to next step. If communication with DDM and PCM is not established, diagnose communication problem with class 2 device. See SELF-DIAGNOSTIC SYSTEM in appropriate BODY CONTROL MODULES article.
Select display DTC function for DDM and PCM. Record all displayed DTCs, status of displayed DTCs and module that set the DTC. If DTCs are displayed, perform appropriate test. See DIAGNOSTIC TROUBLE CODE INDEX table. If no DTCs are displayed, perform system operation check. See SYSTEM OPERATION CHECK under TROUBLE SHOOTING.

DIAGNOSTIC TROUBLE CODE INDEX

DTC

Description

Mirror Switch Right Input Stuck High

Mirror Switch Left Input Stuck High

Mirror Switch Up Input Stuck High

Mirror Switch Down Input Stuck High

B1656, B1982 Or B1983

⁽¹⁾

Memory 1 Switch Failed

Memory 2 Switch Failed

Memory Exit Switch Failed

PXXXX

⁽²⁾

Loss Of PDM Serial Data

Loss Of RDM Serial Data

Loss Of DDSA Serial Data

UXXXX

⁽³⁾

⁽¹⁾	See appropriate BODY CONTROL MODULES article.

⁽²⁾	For any DTC beginning with the letter "P", see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.

⁽³⁾	For any DTC beginning with the letter "U", diagnose communication problem with class 2 device. See SELF-DIAGNOSTIC SYSTEM in appropriate BODY CONTROL MODULES article.