DTC P26CA-14: Engine Coolant Pump Circuit Short to Ground or Open [08/2020 - ]: Procedure

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1. Disconnect the engine water pump assembly (water inlet housing) connector.
2. Turn the ignition switch to ON.
3. Measure the resistance according to the value(s) in the table below.

   Standard

   Tester Connection	Condition	Specified Condition
   C23-2 (SWP) - Body ground	Ignition switch ON	Resistance fluctuates*

   HINT: 

   • *: When the connector of the engine water pump assembly is disconnected, the ECM will enter fail-safe mode. When the ECM is in fail-safe mode, a continuous duty signal will be output and the resistance will fluctuate as the transistor inside the ECM is turned on an off.
   • If the resistance fluctuates while the ECM is in fail-safe mode after the connector of the engine water pump assembly is disconnected, it can be determined that the transistor is operating.
   • If the transistor does not operate, the ECM may be malfunctioning.
   • If the resistance fluctuates after turning the ignition switch to ON, it can be determined that the ECM is in fail-safe mode.

   Result

   Proceed to
   OK
   NG

Result: 

NG 

REPLACE ECM 

Refer to REMOVAL [08/2020 - 12/2021] , or refer to REMOVAL [12/2021 - 10/2022] , or refer to REMOVAL [10/2022 - 10/2023] , or refer to REMOVAL [10/2023 - ]

Result: 

OK 

See step  2

1. Disconnect the engine water pump assembly (water inlet housing) connector.
2. Disconnect the ECM connector.
3. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   C23-2 (SWP) - C45-50 (WPO)	Always	Below 1 Ω
   C23-2 (SWP) or C45-50 (WPO) - Body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

Result: 

OK 

REPLACE ENGINE WATER PUMP ASSEMBLY (WATER INLET HOUSING) 

Refer to REMOVAL [08/2020 - 10/2022] , or refer to REMOVAL [10/2022 - ]

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR