LEMON Manuals: Even more car manuals for everyone
Home >> Chevrolet >> 2017 >> Spark LT, Automatic CVT Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 81 (Engine Controls And Fuel - 1.6L (LWC) - DTC P0243 To DTC P2635 And Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> DTC P2122, P2123, P2127, P2128, or P2138 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.
  1. Ignition OFF and all vehicle systems OFF, disconnect the harness connector at the B107 Accelerator Pedal Position Sensor. It may take up to 2 minutes for all vehicle systems to power down.
  2. Test for less than 5 Ω between the appropriate low reference circuit terminal listed below and ground.
    • APP sensor 1 low reference circuit terminal 4
    • APP sensor 2 low reference circuit terminal 5
    • If 5 Ω or greater 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K20 Engine Control Module.
    • Go to next step: If less than 5 Ω 
  3. Ignition ON.
  4. Test for 4.8 - 5.2 V between the appropriate 5 V reference circuit terminal listed below and ground.
    • APP sensor 1 5 V reference circuit terminal 2
    • APP sensor 2 5 V reference circuit terminal 1
    • If less than 4.8 V 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the 5 V reference circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the 5 V reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K20 Engine Control Module.
    • If greater than 5.2 V 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
    2. Test for less than 1 V between the 5 V reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K20 Engine Control Module.
    • Go to next step: If between 4.8 - 5.2 V 
  5. Verify the scan tool APP sensor 1 and APP sensor 2 voltage parameters are less than 0.3 V.
    • If 0.3 V or greater 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module, ignition ON.
    2. Test for less than 1 V between the signal circuit terminal listed below and ground.
    • APP sensor 1 signal circuit terminal 3
    • APP sensor 2 signal circuit terminal 6
    • If 1 V or greater, repair the short to voltage on the circuit.
    • If less than 1 V, replace the K20 Engine Control Module.
    • Go to next step: If less than 0.3 V 
  6. Install a 3 A fused jumper wire between the appropriate signal circuit terminal listed below and the 5 V reference circuit terminal 1.
    • APP sensor 1 signal circuit terminal 3
    • APP sensor 2 signal circuit terminal 6
  7. Verify the scan tool APP sensor 1 or APP sensor 2 voltage parameter is greater than 4.8 V.
    • If 4.8 V or less 
    1. Ignition OFF, disconnect the harness connector at the K20 Engine Control Module.
    2. Test for infinite resistance between the signal circuit terminal and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K20 Engine Control Module.
    • Go to next step: If greater than 4.8 V 
  8. Test or replace the B107 Accelerator Pedal Position Sensor.
scientia non olet · About LEMON Manuals