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Home >> Chevrolet >> 2020 >> Malibu LS >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 11 (Automatic Transmission - 9T50 (M3E) - Diagnostic Information And Procedures) >> Diagnostic Information and Procedures >> DTC P0658, P0659, P2727, P2729, P2730, P2736, P2738, P2739, P2826, P2827, P282F, or P2830 >> Circuit/System Testing

Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.
  1. Ignition/Vehicle - Off
  2. Disconnect the electrical connector: X1 @ T12 Automatic Transmission Assembly
  3. NOTE:

    All testing for this procedure is performed on the control module K71 side of the circuit.

  4. Connect a test lamp between the test points: Control circuit terminal 15 & Ground
  5. Ignition - On / Vehicle - In Service Mode
  6. NOTE:

    If unable to perform the scan tool control function due to Device Limits Exceeded and/or DTC Present, jumper the component B14A circuits between the component T12 connector and the X1 harness connector. - Connect a 3 A fused jumper wire between the test points:

    • 9 V Reference circuit terminal 7 X1 (harness side) & 9 V Reference circuit terminal 7 X1 (component side)
    • Signal circuit terminal 6 X1 (harness side) & Signal circuit terminal 6 X1 (component side)
  7. Perform the scan tool control function: High Side Driver 1 - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Connect the electrical connector: T12 Automatic Transmission Assembly
    2. Ignition/Vehicle - Off
    3. Disconnect the electrical connector:
      • K71 Transmission Control Module
      • T12 Automatic Transmission Assembly
    4. Test for infinite resistance between the test points: Control circuit terminal 15 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    5. Test for less than 2 ohms between the test points: Control circuit terminal 15 @ Component harness & The other end of the circuit @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • If less than 2 ohms - Replace the component: K71 Transmission Control Module
    • If the test lamp is always On 
    1. Connect the electrical connector: T12 Automatic Transmission Assembly
    2. Ignition/Vehicle - Off
    3. Disconnect the electrical connector:
      • K71 Transmission Control Module
      • T12 Automatic Transmission Assembly
    4. Ignition - On / Vehicle - In Service Mode
    5. Test for less than 1 V between the test points: Control circuit terminal 15 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component: K71 Transmission Control Module
    • Go to next step: If the test lamp turns On and Off 
  8. Verify DTC P0658, P0659 is not set.
    • If the DTC is set 

      Refer to step 9

    • Go to next step: If the DTC is not set 
  9. Connect a test lamp between the test points:
    • { P2727, P2729, P2730 } Control circuit terminal 5 @ Component harness & Control circuit terminal 15 @ Component harness
    • { P2736, P2738, P2739 } Control circuit terminal 4 @ Component harness & Control circuit terminal 15 @ Component harness
    • { P2826, P2827 } Control circuit terminal 3 @ Component harness & Control circuit terminal 15 @ Component harness
    • { P282F, P2830 } Control circuit terminal 2 @ Component harness & Control circuit terminal 15 @ Component harness
  10. Perform the scan tool control function: Transmission Control Solenoid Valve 5, 6, 9, 10 - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp is always Off 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector: K71 Transmission Control Module
    3. Test for less than 2 ohms between the test points:
      • { P2727, P2729, P2730 } Control circuit terminal 5 @ Component harness & The other end of the circuit @ Control module harness
      • { P2736, P2738, P2739 } Control circuit terminal 4 @ Component harness & The other end of the circuit @ Control module harness
      • { P2826, P2827 } Control circuit terminal 3 @ Component harness & The other end of the circuit @ Control module harness
      • { P282F, P2830 } Control circuit terminal 2 @ Component harness & The other end of the circuit @ Control module harness
      • If 2 ohms or greater - Repair the open/high resistance in the circuit.
      • Go to next step: If less than 2 ohms
    4. Ignition - On / Vehicle - In Service Mode
    5. Test for less than 1 V between the test points:
      • { P2727, P2729, P2730 } Control circuit terminal 5 @ Component harness & Ground
      • { P2736, P2738, P2739 } Control circuit terminal 4 @ Component harness & Ground
      • { P2826, P2827 } Control circuit terminal 3 @ Component harness & Ground
      • { P282F, P2830 } Control circuit terminal 2 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component: K71 Transmission Control Module
    • If the test lamp is always On 
    1. Ignition/Vehicle - Off
    2. Disconnect the electrical connector: K71 Transmission Control Module
    3. Test for infinite resistance between the test points:
      • { P2727, P2729, P2730 } Control circuit terminal 5 @ Component harness & Ground
      • { P2736, P2738, P2739 } Control circuit terminal 4 @ Component harness & Ground
      • { P2826, P2827 } Control circuit terminal 3 @ Component harness & Ground
      • { P282F, P2830 } Control circuit terminal 2 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • If infinite resistance - Replace the component: K71 Transmission Control Module
    • Go to next step: If the test lamp turns On and Off 
  11. Remove the component: Control Valve Body Cover
  12. Connect the electrical connector: X1 @ T12 Automatic Transmission Assembly
  13. Disconnect the appropriate electrical connector: Q77 Transmission Control Solenoid Valve
  14. Connect a test lamp between the test points: Control circuit terminal 2 @ Component harness & Control circuit terminal 1 @ Component harness
  15. Perform the scan tool control function: Transmission Control Solenoid Valve 7, 8 - On and Off

    Verify the test lamp turns On and Off.

    • If the test lamp does not turn On and Off 

      Replace the component: Automatic Transmission Wiring Harness - (JUMPER)

    • Go to next step: If the test lamp turns On and Off 
  16. Test or replace the component: Q77 Transmission Control Solenoid Valve