Diagnostic Procedure
WARNING: This page is about a different car, the 2002 Isuzu Trooper. However, it is still accessible from the selected car via links, so may be relevant.
- Perform ON-BOARD DIAGNOSTIC II SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM. After performing OBD-II system check, go to next step.
- Turn ignition off. Disconnect APS 10-pin harness connector. APS is located on accelerator pedal. Check for poor, loose or corroded connections in APS sensor connection. If problem is found, repair as necessary. After repair is complete, see VERIFYING VEHICLE REPAIR under SELF-DIAGNOSTIC SYSTEM. If no problem is found, go to next step.
- Check for open or short circuit in all circuits between APS and PCM. See WIRING DIAGRAMS article. If problem is found, repair as necessary. After repair is complete, see VERIFYING VEHICLE REPAIR under SELF-DIAGNOSTIC SYSTEM. If no problem is found, go to next step.
- Replace APS. See REMOVAL, OVERHAUL & INSTALLATION article. After repair, go to next step.
- Start engine and run until normal operating temperature is achieved (minimum 176°F 80°C). Turn ignition on. Using scan tool, observe APS 1, 2 and 3 angle parameter. While slowly opening throttle APS readings should change steadily and evenly as specified. See ACCELERATOR POSITION SENSOR VALUES table. If APS parameters do not change as specified, go to next step.ACCELERATOR POSITION SENSOR VALUES
Accelerator Position Sensor Specification Accelerator Position Sensor 1 Closed Throttle 9-17 % Wide Open Throttle 83-91 % Accelerator Position Sensor 2 Closed Throttle 83-91 % Wide Open Throttle 9-17 % Accelerator Position Sensor 3 Closed Throttle 83-91 % Wide Open Throttle 30-38 % - Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE REPLACEMENT under POWERTRAIN CONTROL MODULE. Use scan tool to clear DTC and verify repair.