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Hybrid/EV Battery Pack Coolant Pump Malfunction - DTC P0C47, P0C4A or P1F18

The hybrid/EV battery pack coolant pump circulates coolant through the drive motor battery coolant radiator, drive motor battery coolant cooler and the hybrid/EV battery pack to control the temperature of the hybrid/EV battery pack. An enable signal from the hybrid/EV powertrain control module 2 to the hybrid/EV battery pack coolant pump provides overall control of the pump. When this circuit is high, the pump can operate. The pump is controlled with a pulse-width modulated signal from the hybrid/EV powertrain control module 2 to the hybrid/EV battery pack coolant pump. The higher the duty cycle the higher the pump speed. The hybrid/EV battery pack coolant pump provides a hard-wired pulse-width modulated feedback signal to the hybrid/EV powertrain control module 2. During normal operation, this feedback signal provides pump speed information to the hybrid/EV powertrain control module 2. The hybrid/EV battery pack coolant pump has some self-diagnostic capability. If the hybrid/EV battery pack coolant pump determines there is an internal fault it provides this information on this same feedback circuit instead of pump speed information.

P0C47

P0C4A

P1F18

The 12 V battery voltage is greater than or equal to 9 V.

P0C47

The hybrid/EV powertrain control module 2 detects the Coolant Pump Control circuit is open, shorted to voltage or shorted to earth.

P0C4A

The hybrid/EV powertrain control module 2 did not see the battery inlet temperature fall fast enough during the 18 second test period. The hybrid/EV powertrain control module 2 did not detect a decrease of 2° C (3.6° F) in 4 seconds within the 18 second test period.

P1F18

The hybrid/EV powertrain control module 2 detects the Coolant Pump Enable circuit is open, shorted to voltage or shorted to earth.

DTCs P0C47, P0C4A and P1F18 are type B DTCs.

DTCs P0C47, P0C4A and P1F18 are type B DTCs.

Schematic Reference

Hybrid Cooling Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Hybrid Cooling System Description and Operation

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

1. Vehicle in Service Mode, verify that DTC P0C43, P0C44, P0C45, P0CE0, P0CE2, P0CE3, P0D0A, P0D11, P1EBC, P1EC3, P1EC4, P1EC5, P1EC6, P1EC7 or P1EC8 is not set.

⇒	If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle

2. Vehicle in Service Mode, with the pump is disabled and not running, verify the scan tool parameters listed below:

•	Hybrid/EV Battery Pack Coolant Pump Command is less than 10%.

•	Hybrid/EV Battery Pack Coolant Pump Feedback is 0%.

•	Hybrid/EV Battery Pack Coolant Pump Speed is 25 RPM.

3. Vehicle OFF, connect the charge cord set. With the vehicle in Charge Mode, pump enabled and not running, verify the scan tool parameters listed below:

•	Hybrid/EV Battery Pack Coolant Pump Command is 10%.

•	Hybrid/EV Battery Pack Coolant Pump Feedback to be 50% +/-5%.

•	Hybrid/EV Battery Pack Coolant Pump Speed is 50 RPM.

Note: The vehicle must be in Charge Mode and the pump is enabled and not running before proceeding to the next step.

4. Vehicle in Service Mode, command the Hybrid/EV Battery Pack Coolant Pump Heater to 90 kW with a scan tool. Observe the Hybrid/EV Battery Pack Coolant Pump Temperature Sensor 1 parameter. The temperature reading should rise after a 15 second delay, +/- 10 seconds, to above 54° C +/-5° C (129.2° F +/-10°).
5. With the pump enabled and running with the Hybrid/EV Battery Pack Coolant Pump Temperature Sensor 1 parameter above 54° C +/-5° C (129.2° F +/-10°), verify the scan tool parameters listed below:

•	Hybrid/EV Battery Pack Coolant Pump Command to be greater than 10%.

•	Hybrid/EV Battery Pack Coolant Pump Feedback to be 50% +/-5%.

•	Hybrid/EV Battery Pack Coolant Pump Speed is greater than 50 RPM.

6. Verify that the Hybrid/EV Battery Pack Coolant Pump Temperature Sensor 1 parameter dropped to below 40° C (104° F) after a 15 second delay, +/- 10 seconds, with the pump running.

⇒	The Hybrid/EV Battery Pack Coolant Pump Temperature Sensor 1 parameter did not drop to below 40° C (104° F). Refer to Hybrid/EV Battery Cooling Diagnostic

Danger: Any hybrid/EV battery pack replacement shall be performed by High-Voltage Qualified Technicians only. The replacement procedure can be found in the service instruction and must be strictly followed at all times. The High-Voltage Qualified Technician is responsible for adherence to the manufacturer's service instructions as well as current national legal regulations. If the hybrid/EV battery pack needs to be replaced contact the Technical Assistance Centre for further instructions prior to removal of the battery pack.

1. Vehicle in Service Mode, verify that DTC P0C43, P0C44, P0C45, P1EC5, P1EC6, U0111, U185B, or U2602 is not set.

⇒	If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .

2. Ignition OFF, disconnect the harness connector at the G37 hybrid/EV battery pack coolant pump.
3. Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Test for less than 5 Ω between the ground circuit terminal 4 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

4. Connect a test lamp between the B+ circuit terminal 5 and earth circuit terminal 4.
5. Vehicle in Service Mode, verify that a test lamp illuminates between the B+ circuit terminal 5 and earth circuit terminal 4.

⇒	If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal and the B+ circuit fuse is open, test or replace the G37 hybrid/EV battery pack coolant pump.

6. Connect a test lamp between the enable circuit terminal 1 and earth circuit terminal 4.
7. Command the Hybrid Battery Pack Coolant Pump Command OFF (10%) and ON (90%) with a scan tool. Verify the test lamp turns OFF and ON when changing between the commanded states.

⇒	If the test lamp is always illuminated at 10%, test the pump enable circuit for a short-circuit to voltage. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.

⇒	If the test lamp does not illuminate at 90%, test the pump enable circuit for a short-circuit to earth or an open-circuit/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.

8. Connect a test lamp between the control circuit terminal3 and the B+ circuit terminal 5.
9. Command the Hybrid Battery Pack Coolant Pump Command ON between 20% and 90% with a scan tool. Verify that a test lamp changes illumination between bright (20%) and dim (90%) between the control circuit terminal 3 and the B+ circuit terminal 5.

⇒	If the test lamp is always dim or does not illuminate, test the control circuit for a short-circuit to voltage or an open-circuit/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.

⇒	If the test lamp is always bright, test the control circuit for a short-circuit to earth. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.

10. Verify the scan tool Hybrid/EV Battery Pack Coolant Pump Feedback parameter is less than 10%.

⇒	If greater than the specified range, test the feedback circuit terminal 2 for a short-circuit to earth. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.

11. Install a 3 A fused jumper wire between the feedback circuit terminal 2 and the ground circuit terminal 4. Verify that the scan tool, Hybrid/EV Battery Pack Coolant Pump Feedback parameter is greater than 90%.

⇒	If less than the specified range, test the feedback circuit for a short-circuit to voltage or an open-circuit/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2.

12. If all circuits test normal, replace the G37 hybrid/EV battery pack coolant pump.

Perform the Diagnostic Repair Verification after completing the repair.