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Circuit/System Testing

NOTE:

If a carbon pile tester and ammeter is available, refer to With Carbon Pile Tester section. Otherwise, refer to Without Carbon Pile Tester section.

With Carbon Pile Tester

    NOTE:

    Requires carbon pile tester rated to a minimum 200 amps along with either a built-in ammeter or a clamp-on ammeter.

  1. Vehicle Power Mode State: Service/Run 
  2. Verify DTC P1F59, P1F5A, P1F5B, P1F5D, or P1F5E is not set
    • Go to next step: If no DTC is set 
  3. Inspect the F1UB 350A fuse at the X50B Battery Distribution Engine Compartment Fuse Block for being open.
    • If the fuse is open
    • Go to step; If the test lamp does not illuminate and the circuit fuse is open
    • Go to next step: If the fuse is not open
  4. Verify a test lamp illuminates between the 12V B+ circuit ring terminal X6 at the T18 Battery Charger and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Remove the test lamp and disconnect the B+ cable at the T18 Battery Charger.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit 242.
      • If less than 2 Ω, verify the mega fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Remove the test lamp and disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection
    2. Disconnect the T18 Battery Charger B+ cable.
    3. Test for infinite resistance between the B+ circuit 242 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit 242.
      • If infinite resistance replace the T18 Battery Charger.
    • Go to next step: If the test lamp illuminates 
    5. NOTE:

    The vehicle must be capable of providing high voltage in order for the 14V power module to provide 12V current.

  5. Verify that no K16A Battery Energy Control Module or B110 Battery Monitor Module DTCs are set that would cause a charging system concern.
    • Go to next step: If no DTC is set 
  6. Vehicle OFF.
  7. Test for 12.4 V or greater at room temperature across the C1 Battery terminals 12 minutes after turning the vehicle OFF.
    • Go to next step: If within the specified range 
    8. NOTE:

    If using a clamp-on ammeter, place it around the C1 Battery negative cable.

  8. Connect a carbon pile tester to the C1 Battery.
  9. Vehicle ON, turn all accessories off. Observe the voltage reading on the tester. The voltage should read between 12.6 - 15.5 V.
  10. Adjust the carbon pile tester so that the ammeter is reading 200 amps.
  11. Verify the voltage reading remains between 12.6 - 15.5 V.
    • If not in the specified range 
    1. Disconnect the X1 harness connector at the T18 battery charger, vehicle ON.
    2. Test for 3.0 - 5.5V between the control circuit terminal X1-02 and ground.
      • If less than 3.0 V
      1. Vehicle OFF, wait 12 minutes and then disconnect the harness connectors at the K16A battery energy control module.
      2. Test for less than 2Ω in the control circuit end to end.
        • If greater than 2 ohms

          Repair the open/high resistance in the circuit.

        • Go to next step: If less than 2 ohms
      3. K16A Battery Energy Control Module 1 - Replace
      • Go to next step: If within 3.0 - 5.5 V
    3. T18 Battery Charger - Replace
    • Go to next step: If within the specified range 
  12. All OK.

Without Carbon Pile Tester

  1. Vehicle On.
  2. Verify DTC P1F59, P1F5A, P1F5B, P1F5D, or P1F5E is not set
    • Go to next step: If no DTC is set 
  3. Inspect the F1UB 350A fuse at the X50B Battery Distribution Engine Compartment Fuse Block for being open.
    • If the fuse is open
    • Go to step; If the test lamp does not illuminate and the circuit fuse is open
    • Go to next step: If the fuse is not open
  4. Verify a test lamp illuminates between the 12V B+ circuit ring terminal X6 at the T18 Battery Charger and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Remove the test lamp and disconnect the B+ cable at the T18 Battery Charger.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit 242.
      • If less than 2 Ω, verify the mega fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Remove the test lamp and disconnect the battery negative cable. Refer to Battery Negative Cable Disconnection and Connection
    2. Disconnect the T18 Battery Charger B+ cable.
    3. Test for infinite resistance between the B+ circuit 242 and ground.
      • If less than infinite resistance, repair the short to ground on the circuit 242.
      • If infinite resistance replace the T18 Battery Charger.
    • Go to next step: If the test lamp illuminates 
    5. NOTE:

    The vehicle must be capable of providing high voltage in order for the 14V power module to provide 12V current.

  5. Verify that no K16A Battery Energy Control Module or B110 Battery Monitor Module DTCs are set that would cause a charging system concern.
    • Go to next step: If no DTC is set 
  6. Vehicle OFF, wait 12 minutes.
  7. Test for 12V or greater at room temperature across the C1 Battery terminals.
    • Go to next step: If within the specified range 
  8. Vehicle Power Mode state - Service/Run - Propulsion Active Vehicle On
  9. Verify the scan tool Ignition and Start Signal parameter continually increases when controlling the 14V Power Module Setpoint from 10 - 80% with a scan tool. It may take up to 10 s for the battery voltage to stabilize between each setpoint change.
  10. Scan Tool - K16 Battery Energy Control Module - Control Functions - Low Voltage Circuit Enable
    • If the battery voltage does not continually increase 
    1. Disconnect the X1 harness connector at the T18 Battery Charger, vehicle ON.
    2. Test for 3.0 - 5.5 V between the control circuit terminal X1-02 and ground.
      • If less than 3.0 V 
      1. Vehicle OFF, disconnect the harness connectors at the K16A battery energy control module.
      2. Test for less than 2 Ω in the control circuit end to end.
        • If greater than 2 ohms

          Repair the open/high resistance in the circuit.

        • Go to next step: If less than 2 ohms
      3. K16A Battery Energy Control Module 1 - Replace
      • Go to next step: If within 3.0 - 5.5 V
    3. T18 Battery Charger - Replace
    • Go to next step: If the battery voltage continually increases 
  11. All OK.
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