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Home >> Suzuki >> 2003 >> XL-7 Base, RWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 4 (Engine Controls - Self-Diagnostics) >> Diagnostic Tests >> DTC P1280: Accelerator Position Sensor 2 - 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 2 (APS2) angle parameter while slowly opening throttle. At idle position, APS2 value should equal 83-91 percent, and decrease to 9-17 percent at wide open throttle. Readings should change steadily and evenly. If APS2 does not operate as specified, go to next step. If APS2 operates as specified, go to step  4.
  3. Using scan tool, retrieve DTCs. If DTC P1280 is set, go to step  8. If DTC P1280 is not set, check for intermittent problem. See DIAGNOSTIC AIDS .
  4. Disconnect APS 10-pin harness connector. APS is located on accelerator pedal. Connect test light between APS2 harness connector terminals No. 8 (Green wire) and No. 9 (Yellow wire). See Figure. On scan tool, observe APS2 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 APS2 signal circuit. Check for high resistance in APS2 ground circuit between PCM and APS. Check for poor connections in APS2 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 APS2 signal and 5-volt supply circuit. Check for high resistance in APS2 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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