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Home >> Suzuki >> 2002 >> XL-7 Plus >> Repair and Diagnosis >> External Pages >> Different car >> Section 6 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P1285: Accelerator Position Sensor 3 - Circuit Malfunction >> Diagnostic Procedure
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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.
  1. Perform ON-BOARD DIAGNOSTIC II SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing OBD-II system check, go to next step.
  2. Start engine and run until normal operating temperature is achieved (minimum 176°F 80°C). Turn ignition on, engine off. Using scan tool, observe Accelerator Position Sensor 3 (APS3) angle parameter while slowly opening throttle. At idle position, APS3 value should equal 83-91 percent, and decrease to 30-38 percent at wide open throttle. Readings should change steadily and evenly. If APS3 does not operate as specified, go to next step. If APS3 operates as specified, go to step  4.
  3. Using scan tool, retrieve DTCs. If DTC P1285 is set, go to step  8. If DTC P1285 is not set, check for intermittent problem. See DIAGNOSTIC AIDS .
  4. Turn ignition off. Disconnect APS 10-pin harness connector. APS is located on accelerator pedal. Connect test light between APS3 harness connector terminals No. 1 (Orange wire) and No. 6 (Blue/Green wire). See Figure. On scan tool, observe APS3 voltage parameter. If voltage parameter is as specified, go to next step. If voltage parameter is not as specified, go to step  6.
  5. Check for short to voltage in APS3 signal circuit. Check for high resistance in APS3 ground circuit between PCM and APS. Check for poor connections in APS3 ground circuit. 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.
  6. Check for poor connections in APS3 signal and 5-volt supply circuit. Check for high resistance in APS3 signal and 5-volt supply circuit between PCM and APS. 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.
  7. Replace APS. See REMOVAL, OVERHAUL & INSTALLATION article. After repair is complete, see VERIFYING VEHICLE REPAIR  under SELF-DIAGNOSTIC SYSTEM.
  8. Replace and reprogram PCM. See POWERTRAIN CONTROL MODULE REPLACEMENT  under POWERTRAIN CONTROL MODULE. Use scan tool to clear DTC and verify repair.
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