Diagnostic Test

WARNING: This page is about a different variant/trim than selected.

TEST FOR INTERMITTENT CONDITION
1. Ignition on
2. With the scan tool, record and erase BPCM DTCs.
3. Turn the ignition off. Wait 3 minutes.
4. Turn the ignition on. Wait 3 minutes.
5. With the scan tool, read DTCs.
  Does the scan tool display this DTC as active?
  
  Yes
  - Go To 2
  No
  - The condition or conditions that originally set this DTC are not present at this time. Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
(H378) BATTERY COOLANT HEATER CONTROL CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Battery Coolant Heater harness connector.
3. Disconnect the High Voltage Battery Pack C3 low voltage harness connector.
4. Measure the resistance between ground and the (H378) Battery Coolant Heater Control circuit in the Battery Coolant Heater harness connector.
  Is the resistance above 1000 Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (H378) Battery Coolant Heater Control circuit for a short to ground.
  - Perform the BATTERY PACK CONTROL MODULE (BPCM) VERIFICATION TEST. Refer to BPCM VERIFICATION TEST .
(H378) BATTERY COOLANT HEATER CONTROL CIRCUIT SHORTED TO THE (H374) BATTERY COOLANT HEATER RETURN CIRCUIT
1. Measure the resistance between the (H378) Battery Coolant Heater Control circuit and the (H374) Battery Coolant Heater Return circuit in the Battery Coolant Heater harness connector.
  Is the resistance above 1000 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (H378) Battery Coolant Heater Control circuit for a short to the (H374) Battery Coolant Heater Return circuit.
  - Perform the BATTERY PACK CONTROL MODULE (BPCM) VERIFICATION TEST. Refer to BPCM VERIFICATION TEST .
BATTERY COOLANT HEATER
1. Turn the ignition off.
2. Reconnect the High Voltage Battery Pack C3 low voltage harness connector.
3. Turn the ignition on.
4. Using the scan tool, go to Actuators in EVCU View and actuate the Battery Coolant Heater Duty Cycle to the maximum allowable percentage.
5. Using a 12-volt test light connected to ground, check the (H378) Battery Coolant Heater Control circuit in the Battery Coolant Heater harness connector.
  NOTE:
  The test light should flash dimly.
6. With the scan tool, actuate the Battery Coolant Heater control to OFF.
7. Using a 12-volt test light connected to ground, check the (H378) Battery Coolant Heater Control circuit in the Battery Coolant Heater harness connector.
  NOTE:
  The test light should not be illuminated with the control actuated OFF.
  
  Does the test light flash dimly with the actuator ON and not illuminated with the actuator OFF?
  
  Yes
  - Replace the Battery Coolant Heater in accordance with the Service Information. Refer to HEATER, BATTERY COOLANT (BCH), REMOVAL .
  - Perform the BATTERY PACK CONTROL MODULE (BPCM) VERIFICATION TEST. Refer to BPCM VERIFICATION TEST .
  No
  - Go To 5
BATTERY PACK CONTROL MODULE (BPCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Battery Coolant Heater and the High Voltage Battery Pack.
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the BATTERY PACK CONTROL MODULE (BPCM) VERIFICATION TEST. Refer to BPCM VERIFICATION TEST .
  No
  - Replace the High Voltage Battery Pack in accordance with the Service Information. Refer to BATTERY, HIGH-VOLTAGE, REMOVAL .
  - Perform the BATTERY PACK CONTROL MODULE (BPCM) VERIFICATION TEST. Refer to BPCM VERIFICATION TEST .