LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 2022 >> Hummer EV >> Repair and Diagnosis >> Electrical >> Charging Systems >> Plug-In Charging System >> Diagnostic Information and Procedures >> DTC P3027-P3029 >> Circuit/System Testing
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Circuit/System Testing

NOTE:

Circuit/System Verification must be performed before proceeding with Circuit/System Testing.

  1. Ensure the Battery Charger Coupler Lock is in the UNLOCKED position.
  2. Vehicle Off.
  3. Disconnect the electrical connector: X98 Battery Charger Coupler
  4. Test for less than 5 ohms between the test points: Low Reference circuit terminal X2-11 & Ground
    • If 5 ohms or greater 
    1. Disconnect the appropriate electrical connector: K16A Battery Energy Control Module 1
    2. Test for less than 2 ohms between the test points: Low Reference circuit terminal X2-11 @ 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: K16A Battery Energy Control Module 1
    • Go to next step: If less than 5 ohms 
  5. Vehicle On, in Service Mode.
  6. Test for 4.8 to 5.2 V between the test points: Signal circuit terminal X2-10 & Ground
    • If less than 4.8 V 
    1. Vehicle Off.
    2. Disconnect the appropriate electrical connector: K16A Battery Energy Control Module 1
    3. Test for infinite resistance between the test points: Signal circuit terminal X2-10 @ Component harness & Ground
      • If less than infinite resistance - Repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    4. Test for less than 2 ohms between the test points: Signal circuit terminal X2-10 @ 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: K16A Battery Energy Control Module 1
    • If greater than 5.2 V 
    1. Vehicle Off.
    2. Disconnect the appropriate electrical connector: K16A Battery Energy Control Module 1
    3. Vehicle On, in Service Mode.
    4. Test for less than 1 V between the test points: Signal circuit terminal X2-10 @ Component harness & Ground
      • If 1 V or greater - Repair the short to voltage on the circuit.
      • If less than 1 V - Replace the component: K16A Battery Energy Control Module 1
    • Go to next step: If between 4.8 and 5.2 V 
  7. Test or replace the component: X98 Battery Charger Coupler