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Enabling Conditions And Possible Causes-Coolant Pumps

WARNING: This page is about a different car, the 2024 RAM ProMaster EV. However, it is still accessible from the selected car via links, so may be relevant.

MONITORING CONDITIONS
P0C73-00-MOTOR ELECTRONICS COOLANT PUMP "A" CONTROL PERFORMANCE	Continuous when the pump is commanded on. Ignition is in the Run position.
P1EA2-00-MOTOR ELECTRONICS COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Continuous when the pump is commanded on. Ignition is in the Run position.
P1EA4-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Continuous when the pump is commanded on. Ignition is in the Run position.
P1EA5-00-COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Continuous when the pump is commanded on. Ignition is in the Run position.
P2601-00-ELECTRIC COOLANT PUMP CONTROL CIRCUIT PERFORMANCE/STUCK OFF	Continuous when the pump is commanded on. Ignition is in the Run position.
P2B28-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" PERFORMANCE	Continuous when the pump is commanded on. Ignition is in the Run position.
P2B29-00-HYBRID/EV BATTERY PACK COOLANT PUMP "A" OVERSPEED /AIR IN SYSTEM	Continuous when the pump is commanded on. Ignition is in the Run position.
P2D01-00-MOTOR ELECTRONICS COOLANT PUMP "A" OVERSPEED/AIR IN SYSTEM	Continuous when the pump is commanded on. Ignition is in the Run position.
U02AE-00-LOST COMMUNICATIONS WITH HYBRID/EV BATTERY COOLANT PUMP	Continuous when the pump is commanded on. Ignition is in the Run position.
U0623-00-LOST COMMUNICATION WITH COOLANT PUMP "A"	Continuous when the pump is commanded on. Ignition is in the Run position.
U0646-00-LOST COMMUNICATION WITH MOTOR ELECTRONICS COOLANT PUMP "A"	Continuous when the pump is commanded on. Ignition is in the Run position.

FAULT SETTING CRITERIA
P0C73-00-MOTOR ELECTRONICS COOLANT PUMP "A" CONTROL PERFORMANCE	The Electronic Vehicle Control Unit (EVCU) detects that the Electric Drive Motor (EDM) Coolant Pump is not operating at the requested pump speed.
P1EA2-00-MOTOR ELECTRONICS COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	The Electronic Vehicle Control Unit (EVCU) detects that the temperature sensor inside the Electric Drive Motor (EDM) Coolant Pump is not providing expected temperature reading as compared with other temperature sensors.
P1EA4-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	The Electronic Vehicle Control Unit (EVCU) detects that the temperature sensor inside the Battery Coolant Pump is not providing expected temperature reading as compared with other temperature sensors.
P1EA5-00-COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	The Electronic Vehicle Control Unit (EVCU) detects that the temperature sensor inside the Cabin Heater Electric Coolant Pump is not providing expected temperature reading as compared with other temperature sensors.
P2601-00-ELECTRIC COOLANT PUMP CONTROL CIRCUIT PERFORMANCE/STUCK OFF	The Electronic Vehicle Control Unit (EVCU) detects that the temperature sensor inside the Cabin Heater Electric Coolant Pump malfunction has been detected.
P2B28-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" PERFORMANCE	The Electronic Vehicle Control Unit (EVCU) detects that the Battery Coolant Pump is not operating at the requested pump speed.
P2B29-00-HYBRID/EV BATTERY PACK COOLANT PUMP "A" OVERSPEED /AIR IN SYSTEM	The Electronic Vehicle Control Unit (EVCU) detects that the Battery Coolant Pump has detected a dry run condition based on higher pump speed.
P2D01-00-MOTOR ELECTRONICS COOLANT PUMP "A" OVERSPEED/AIR IN SYSTEM	The Electronic Vehicle Control Unit (EVCU) detects that the Electric Drive Motor (EDM) Coolant Pump has detected a dry run condition based on higher pump speed.
U02AE-00-LOST COMMUNICATIONS WITH HYBRID/EV BATTERY COOLANT PUMP	The Battery Pack Control Module (BPCM) detected loss of communication with the Battery Coolant Pump over the LIN BUS.
U0623-00-LOST COMMUNICATION WITH COOLANT PUMP A	The Electronic Vehicle Control Unit (EVCU) detected loss of communication with the Cabin Heater Electric Coolant Pump over the LIN BUS.
U0646-00-LOST COMMUNICATION WITH MOTOR ELECTRONICS COOLANT PUMP "A"	The Electronic Vehicle Control Unit (EVCU) detected loss of communication with the Electric Drive Motor (EDM) Coolant Pump over the LIN BUS.

DEFAULT AND LIMP-IN ACTIONS
P0C73-00-MOTOR ELECTRONICS COOLANT PUMP "A" CONTROL PERFORMANCE	Malfunction Indicator Lamp (MIL) on. Service High Voltage system warning message on. De-rate eMotor. Request 3-way valve to open and Battery Coolant Pump to run at maximum speed. Send request signal for limp home management.
P1EA2-00-MOTOR ELECTRONICS COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. Driving range is reduced.
P1EA4-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Malfunction Indicator Lamp (MIL) on. Service High Voltage system warning message on. Heater request will be disabled.
P1EA5-00-COOLANT PUMP A TEMPERATURE SENSOR PERFORMANCE	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on.
P2601-00-ELECTRIC COOLANT PUMP CONTROL CIRCUIT PERFORMANCE/STUCK OFF	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. Reduced thermal cooling performance. System torque is limited.
P2B28-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" PERFORMANCE	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. Disable Battery Coolant Heater. Disable EAC for battery cooling.
P2B29-00-HYBRID/EV BATTERY PACK COOLANT PUMP "A" OVERSPEED /AIR IN SYSTEM	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. Disable Battery Coolant Heater. Disable EAC for battery cooling.
P2D01-00-MOTOR ELECTRONICS COOLANT PUMP "A" OVERSPEED/AIR IN SYSTEM	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. The vehicle shall enter the reduced performance mode thus limiting driver torque request.
U02AE-00-LOST COMMUNICATIONS WITH HYBRID/EV BATTERY COOLANT PUMP	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. The vehicle shall enter the reduced performance mode thus limiting driver torque request.
U0623-00-LOST COMMUNICATION WITH COOLANT PUMP "A"	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. The vehicle shall enter the reduced performance mode thus limiting driver torque request. Heater request is disabled.
U0646-00-LOST COMMUNICATION WITH MOTOR ELECTRONICS COOLANT PUMP "A"	Malfunction Indicator Lamp (MIL) on. Service High Voltage System warning message on. The vehicle shall enter the reduced performance mode thus limiting driver torque request.

POSSIBLE CAUSES
P0C73-00-MOTOR ELECTRONICS COOLANT PUMP "A" CONTROL PERFORMANCE	Low system voltage. LIN BUS communication DTCs. Low coolant. Weak B+ feed to Electric Drive Motor (EDM) Coolant Pump. Weak Ground to the Electric Drive Motor (EDM) Coolant Pump. Electric Drive Motor (EDM) Coolant Pump.
P1EA2-00-MOTOR ELECTRONICS COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Low system voltage. LIN BUS communication DTCs. Low coolant. Weak B+ feed to the Electric Drive Motor (EDM) Coolant Pump. Weak Ground to the Electric Drive Motor (EDM) Coolant Pump. Electric Drive Motor (EDM) Coolant Pump.
P1EA4-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Battery Pack Control Module (BPCM) inlet or outlet coolant temperature sensor DTCS present. Low coolant. Internal temperature sensor is open or shorted in the High Battery Coolant Pump. Battery Coolant Pump.
P1EA5-00-COOLANT PUMP "A" TEMPERATURE SENSOR PERFORMANCE	Inlet or outlet coolant temperature sensor DTCS present. Low coolant. Internal temperature sensor is open or shorted in the Electric Cabin Heater Coolant Pump. Electric Cabin Heater Coolant Pump.
P2601-00-ELECTRTIC COOLANT PUMP CONTROL CIRCUIT PERFORMANCE/STUCK OFF	Low system voltage. Low coolant. Weak B+ feed to the Battery Coolant Pump. Weak Ground to Battery Coolant Pump. Battery Coolant Pump.
P2B28-00-HYBRID-EV BATTERY PACK COOLANT PUMP "A" PERFORMANCE	Low system voltage. Low coolant. Weak B+ feed to the Electric Cabin Heater Coolant Pump. Weak Ground to Electric Cabin Heater Coolant Pump. Electric Cabin Heater Coolant Pump.
P2B29-00-HYBRID/EV BATTERY PACK COOLANT PUMP "A" OVERSPEED /AIR IN SYSTEM	Low coolant. Air pockets in the Cooling Loop. Restrictions in the Cooling Loop.
P2D01-00-MOTOR ELECTRONICS COOLANT PUMP "A" OVERSPEED/AIR IN SYSTEM	Low coolant. Air pockets in the Cooling Loop. Restrictions in the Cooling Loop.
U02AE-00-LOST COMMUNICATIONS WITH HYBRID/EV BATTERY COOLANT PUMP	LIN Bus Circuit Open or shorted to the Battery Coolant Pump. Weak B+ feed to the Battery Coolant Pump. Weak Ground to the Battery Coolant Pump. Battery Coolant Pump.
U0623-00-LOST COMMUNICATION WITH COOLANT PUMP "A"	LIN Bus Circuit Open or shorted to the Electric Cabin Heater Coolant Pump. Weak B+ feed to the Electric Cabin Heater Coolant Pump. Weak Ground to the Electric Cabin Heater Coolant Pump. Electric Cabin Heater Coolant Pump.
U0646-00-LOST COMMUNICATION WITH MOTOR ELECTRONICS COOLANT PUMP "A"	LIN Bus Circuit Open or shorted to the Electric Drive Motor (EDM) Coolant Pump. Weak B+ Feed to the Electric Drive Motor (EDM) Coolant Pump. Weak Ground to the Electric Drive Motor (EDM) Coolant Pump. Electric Drive Motor (EDM) Coolant Pump.