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Home >> Suzuki >> 2008 >> Swift + >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls And Fuel - 1.6L - DTC P0630 To DTC P2282 >> DTC P2122, P2123, P2127, P2128, or P2138 >> Circuit/System Testing
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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the accelerator pedal assembly.
  2. Ignition OFF, test for less than 5 ohms of resistance between the appropriate low reference circuit terminal and ground.
    • MT 34 Controller APP1 sensor low reference circuit terminal 5
    • MT 34 Controller APP2 sensor low reference circuit terminal 2
    • Hatchback APP1 sensor low reference circuit terminal 2
    • Hatchback APP2 sensor low reference circuit terminal 4
    • If greater than the specified range, test the low reference circuit for a short to voltage, or an open/high resistance. If the circuit tests normal, replace the ECM.
    3. IMPORTANT: The 5-volt reference circuits are internally and externally connected at the ECM. Other component DTCs may be set. If other DTCs are set, review the electrical schematic and diagnose the applicable circuits and components.
  3. Ignition ON, test for 4.8-5.2 volts between the appropriate 5-volt reference circuit and ground.
    • MT 34 Controller APP1 sensor 5 volt reference circuit terminal 4
    • MT 34 Controller APP2 sensor 5 volt reference circuit terminal 3
    • Hatchback APP1 sensor 5 volt reference circuit terminal 6
    • Hatchback APP2 sensor 5 volt reference circuit terminal 5
    • If less than the specified range, test the 5-volt reference circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the ECM.
    • If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  4. Verify the appropriate APP sensor percentage parameter is at 0%.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.
  5. Install a 3A fused jumper wire between the appropriate signal circuit and the 5-volt reference circuit. Verify the APP sensor percentage parameter is greater than 85 percent.
    • MT 34 Controller APP1 sensor signal circuit terminal 6
    • MT 34 Controller APP2 sensor signal circuit terminal 1
    • Hatchback APP1 sensor signal circuit terminal 1
    • Hatchback APP2 sensor signal circuit terminal 3
    • If less than the specified range, test the appropriate signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
  6. If all circuits test normal, test or replace the accelerator pedal assembly.
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