Test 18: Automatic Transmission Gear Position (PRND321) Display Inaccurate Or Inoperative
- Perform INSTRUMENT PANEL CLUSTER (IPC) DIAGNOSTIC SYSTEM CHECK before proceeding. See INSTRUMENT PANEL CLUSTER (IPC) DIAGNOSTIC SYSTEM CHECK under SYSTEM TEST. If INSTRUMENT PANEL CLUSTER (IPC) DIAGNOSTIC SYSTEM CHECK has been performed, go to next step.
- Turn ignition switch to ON position. Move shift lever through all gear positions. If gear position display identifies correct gear position, check for an intermittent problem caused by poor connections, a break in wire insulation, or a broken wire inside insulation. See WIRING DIAGRAMS . If gear position display does not identify gear position correctly, go to next step.
- Turn ignition switch to OFF position. Connect scan tool to Data Link Connector (DLC). Turn ignition switch to ON position. Using scan tool, select INSTRUMENT PANEL CLUSTER, SPECIAL FUNCTIONS, then PRND321 DISPLAY. Place shift lever in Park. Using scan tool, read PARK SWITCH parameter. If scan tool displays CLOSED, go to next step. If scan tool does not display CLOSED, go to TEST 19: AUTOMATIC TRANSMISSION GEAR POSITION (PRND321) DISPLAY INOPERATIVE .
- Using scan tool, command each gear position on. If gear position display identifies correct gear position, go to appropriate transmission range switch diagnostic test. See appropriate ELECTRONIC CONTROLS article in AUTOMATIC TRANSMISSIONS. If gear position display does not identify gear position correctly, go to next step.
- Replace IPC. See INSTRUMENT PANEL CLUSTER (IPC) under REMOVAL & INSTALLATION. After repair, go to next step.
- Turn ignition switch to ON position. Move shift lever through all gear positions. If gear position display identifies correct gear position, system is okay. If gear position display does not identify correct gear position, return to step 3.