DTC P0C73-96: Motor Electronics Coolant Pump "A" Component Internal Failure [09/2023 - ]: Procedure

Pre-procedure1

• None

• Check for DTCs.

  Powertrain > Hybrid Control > Trouble Codes 

  Result

  Result	Proceed to
  DTCs are not output, or DTCs except the ones in the table below are also output.	A
  Any of the following DTCs including pending DTCs are also output.	B

  Malfunction Content	Relevant DTC
  Microcomputer malfunction	P0606-47	Hybrid/EV Powertrain Control Module Processor Watchdog / Safety MCU Failure
  	P0688-1F	ECM/PCM Power Relay Sense Circuit Intermittent

  HINT: 

  P0C73-96 may be output as a result of the malfunction indicated by the DTCs above.

  1. The chart above is listed in inspection order of priority.
  2. Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

Post-procedure1

• Turn the ignition switch off.

Result: 

B 

GO TO DTC CHART (HYBRID CONTROL SYSTEM). Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2023 - ] 

Result: 

A 

See step  2

Pre-procedure1

• None

• Read the DTCs.

  Powertrain > Engine > Trouble Codes 

  Result

  Result	Proceed to
  P0C73-96 only is output, or DTCs except the ones in the table below are also output.	A
  Any of the following DTCs including pending DTCs are also output.	B

  Malfunction Content	Relevant DTC
  Microcomputer malfunction	P0606-47	Control Module Processor Watchdog/Safety MCU Failure
  Sensor and actuator circuit malfunction	P314A-31	Motor Electronics Coolant Pump "A" No Signal

  HINT: 

  P0C73-96 may be output as a result of the malfunction indicated by the DTCs above.

  1. The chart above is listed in inspection order of priority.
  2. Check DTCs that are output at the same time by following the listed order. (The main cause of the malfunction can be determined without performing unnecessary inspections.)

Post-procedure1

• Turn the ignition switch off.

Result: 

B 

GO TO DTC CHART. Refer to  DIAGNOSTIC TROUBLE CODE CHART [09/2023 - ] 

Result: 

A 

See step  3

HINT: 

• When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.
• When the inverter water pump assembly signal line (SWP - IWPO) is open or its connection is faulty, the inverter water pump assembly is operated forcibly.

Pre-procedure1

• None

• According to the display on the GTS, read the Data List.

  Powertrain > Engine > Data List 

  Tester Display
  Intercooler Water Pump Speed

  Result

  Result	Proceed to
  The value of Intercooler Water Pump Speed is 200 rpm or less	A
  None of the above conditions are met	B

  HINT: 

  When the inverter water pump assembly is not operating, the Data List item "Intercooler Water Pump Speed" displays a value 200 rpm or less.

Post-procedure1

• Turn the ignition switch off.

Result: 

B 

See step  7

Result: 

A 

See step  4

Pre-procedure1

• None

• Clear the DTCs.

  Powertrain > Engine > Clear DTCs 

  Result

  Proceed to
  NEXT

Post-procedure1

• Turn the ignition switch off and wait for at least 30 seconds.

Result: 

NEXT 

See step  5

HINT: 

When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.

Pre-procedure1

• None

• Read the Data List during 85% drive of the inverter water pump assembly.

  Powertrain > Engine > Active Test 

  Active Test Display
  Control the Intercooler Water Pump

  Data List Display
  Intercooler Water Pump Speed
  Intercooler Water Pump

  Result

  GTS Operation	Intercooler Water Pump Speed
  85%	3000 to 9500 rpm

  HINT: 

  • Perform the Active Test with the inverter coolant temperature between -15 and 65°C (5 to 149°F).
  • When the inverter water pump assembly is not operating, the Data List item "Intercooler Water Pump Speed" displays a value 200 rpm or less.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• Turn the ignition switch off.

Result: 

NG 

See step  7

Result: 

OK 

See step  6

1. Read the Freeze Frame Data item "Ambient Temperature" using the GTS.

   Powertrain > Hybrid Control > Trouble Codes 

2. Check if the Freeze Frame Data item "Ambient Temperature" is below the freezing temperature of the HV coolant.

   Result

   Result	Proceed to
   Ambient Temperature value is above freezing temperature of the HV coolant.	A
   Ambient Temperature value is below freezing temperature of the HV coolant.	B

   HINT: 

   • HV coolant (SLLC) with a 30% concentration freezes at -15°C (5°F) and HV coolant (SLLC) with a 50% concentration freezes at -35°C (-31°F).
   • If the HV coolant freezes in the HV radiator or inverter water pump, the coolant temperature in the inverter with converter assembly rises because the HV coolant cannot circulate. As a result, a DTC may be stored.
   • A DTC is stored when the inverter water pump impeller cannot rotate due to freezing of the HV coolant.
   • If DTCs are output due to freezing of the LLC, the problem symptom cannot be reproduced. Check the LLC replacement history and whether the LLC was frozen based on the ambient temperature when the DTCs were stored.

Result: 

A 

See step  13

Result: 

B 

REPLACE HV COOLANT. Refer to  REPLACEMENT [09/2023 - ] 

1. Check the connector connections and contact pressure of the relevant terminals for the ECM connectors.

   HINT: 

   Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2023 - ]

   Refer to REMOVAL [09/2023 - ]

   OK

   The connectors are connected securely and there are no contact pressure problems.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

CONNECT SECURELY 

Result: 

OK 

See step  8

1. Check the connector connections and contact pressure of the relevant terminals for the inverter water pump assembly connector.

   HINT: 

   Refer to ELECTRONIC CIRCUIT INSPECTION PROCEDURE [09/2023 - ]

   Refer to REMOVAL [09/2023 - ]

   OK

   The connector is connected securely, the terminals are not deformed or corroded and there are no contact problems.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

CONNECT SECURELY 

Result: 

OK 

See step  9

Pre-procedure1

• Disconnect the ECM connector.
• Disconnect the inverter water pump assembly connector.

• Measure the resistance according to the value(s) in the table below.

  Standard Resistance

  Tester Connection	Condition	Specified Condition	Result
  C26-45 (IWPO) - C33-3 (SWP)	Ignition switch off	Below 1 Ω	Ω
  C26-45 (IWPO) or C33-3 (SWP) - Body ground and other terminals	Ignition switch off	10 kΩ or higher	kΩ

  HINT: 

  Check the condition (looseness, deterioration, etc.) of the wire to body ground for the inverter water pump assembly.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• Reconnect the inverter water pump assembly connector.
• Reconnect the ECM connector.

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

Result: 

OK 

See step  10

HINT: 

When the auxiliary battery voltage is low, the inverter water pump assembly may not operate.

Pre-procedure1

• Remove the INV W/PMP NO. 2 fuse from No. 1 engine room relay block and No. 1 junction block assembly.

• Read the Data List when the ignition switch is ON.

  Powertrain > Engine > Data List 

  Tester Display
  Intercooler Water Pump Speed

  Result

  Result	Proceed to
  The value of Intercooler Water Pump Speed is 200 rpm or less	A
  None of the above conditions are met	B

Post-procedure1

• Turn the ignition switch off.
• Install the INV W/PMP NO. 2 fuse.

Result: 

B 

REPLACE ECM. Refer to  REMOVAL [09/2023 - ] 

Result: 

A 

See step  11

Pre-procedure1

• Disconnect the C26 ECM connector.
• Turn the ignition switch to ON.

• Measure the voltage according to the value(s) in the table below.

  Standard Voltage

  Tester Connection	Condition	Specified Condition	Result
  C26-45 (IWPO) - Body ground	Ignition switch ON	11 to 14 V	V

  NOTE:

  If the ignition switch is turned to ON with the ECM connectors disconnected, other DTCs will be stored. Be sure to clear the DTCs after the inspection.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• Turn the ignition switch off.
• Reconnect the ECM connector.

Result: 

NG 

See step  13

Result: 

OK 

See step  12

Pre-procedure1

• Disconnect the inverter water pump assembly connector.

• Measure the resistance according to the value(s) in the table below.

  Powertrain > Engine > Active Test 

  Active Test Display
  Control the Intercooler Water Pump

  Data List Display
  Intercooler Water Pump

  Standard Resistance

  Tester Connection	Condition	Specified Condition
  C33-3 (SWP) - Body ground	Active Test OFF → ON	Active Test OFF: Resistance stabilized → ON: Resistance changes*

  HINT: 

  *: The transistor inside the ECM performs duty control according to the Active Test being operated. The resistance of the IWPO terminal changes while the Active Test is on due to duty control. If the resistance is stable while the Active Test is off and changes while the Active Test is on, the transistor is working correctly. If the transistor does not operate when the Active Test is on, there may be a malfunction in the ECM.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• Reconnect the inverter water pump assembly connector.

Result: 

NG 

REPLACE ECM. Refer to  REMOVAL [09/2023 - ] 

Result: 

OK 

See step  13

HINT: 

Refer to REMOVAL [09/2023 - ]

Result

Result: 

NEXT 

See step  14

1. After replacing the inverter water pump assembly, add HV coolant and perform air bleeding.

   HINT: 

   Refer to REPLACEMENT [09/2023 - ]

   Result

   Proceed to
   NEXT

Result: 

NEXT 

END