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Home >> Buick >> 2016 >> Cascada Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 39 (Battery, Charging System And Starting System) >> Diagnostic Information and Procedures >> Stop/Start System Malfunction >> Circuit/System Testing >> Dual Battery Control Module Circuit Malfunction
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Dual Battery Control Module Circuit Malfunction

WARNING: This page is about a different car, the 2016 Chevrolet Malibu Limited. However, it is still accessible from the selected car via links, so may be relevant.
  1. Test for less than 0.5 V between the C1B Battery - Auxiliary positive terminal and B+ circuit connector X4 terminal 1 at the X50D Fuse Block - Battery with the ignition in the START position.
    • If 0.5 V or greater 

      Replace C1B Battery - Auxiliary positive cable.

    • If less than 0.5 V 
  2. Ignition OFF, disconnect the C1 and C1B battery (disconnect negative cable of each battery).
    CAUTION: Do not disconnect the K125 Dual Battery Control Module harness connector with the batteries connected. Leaving the module disconnected for an extended period of time can lead to a significant increase in temperature and damage to the module.
  3. Disconnect the harness connector at the at the K125 Dual Battery Control Module.
  4. Test for less than 10 Ω between ground circuit terminal 4 and ground.
    • If 10 Ω or greater 
    1. Test for less than 2 Ω in the ground circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, repair the open/high resistance in the ground connection.
    • If less than 10 Ω 
  5. Disconnect the F18UA 5A fuse.
  6. Test for infinite resistance between the ignition circuit terminal 3 and B+ terminal of the C1 Battery.
    • If less than infinite resistance 

      Repair the short to voltage on the circuit.

    • If infinite resistance 
  7. Test for infinite resistance between the ignition circuit terminal 3 and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  8. Test for less than 2 Ω in the ignition circuit end to end.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 2 Ω 
  9. Disconnect the X2 harness connector at the K20 Engine Control Module and disconnect the KR27 Starter Relay.
  10. Test for infinite resistance between the control circuit terminal 2 at the K125 Dual Battery Control Module and B+.
    • If less than infinite resistance 

      Repair the short to voltage on the circuit.

    • If infinite resistance 
  11. Test for infinite resistance between the control circuit terminal 2 at the K125 Dual Battery Control Module and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  12. Test for less than 2 Ω in the control circuit end to end.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 2 Ω 
  13. Disconnect the X1 harness connector at the K20 Engine Control Module and disconnect the KR86 Transmission Fluid Pump Relay - Electric/Auxiliary.
  14. Test for infinite resistance between the control circuit terminal 1 at the K125 Dual Battery Control Module and B+.
    • If less than infinite resistance 

      Repair the short to voltage on the circuit.

    • If infinite resistance 
  15. Test for infinite resistance between the control circuit terminal 1 at the K125 Dual Battery Control Module and ground.
    • If less than infinite resistance 

      Repair the short to ground on the circuit.

    • If infinite resistance 
  16. Test for less than 2 Ω in the control circuit end to end.
    • If 2 Ω or greater 

      Repair the open/high resistance in the circuit.

    • If less than 2 Ω 
  17. Test or replace the K125 Dual Battery Control Module.
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