DTC P26CA-14: Engine Coolant Pump Circuit Short to Ground or Open [06/2018 - 08/2020]: Procedure
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- INSPECT ECM (INTERNAL CIRCUIT)
*a Front view of wire harness connector
(to Water Inlet Housing with Water Pump Sub-assembly)- Disconnect the water inlet housing with water pump sub-assembly connector.
- Turn the power switch on (IG).
- Measure the resistance according to the value(s) in the table below.
Standard
Tester Connection Condition Specified Condition C66-2 (SWP) - Body ground Power switch on (IG) Resistance fluctuates* HINT:
- *: When the connector of the water inlet housing with water pump sub-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 water inlet housing with water pump sub-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 power switch on (IG), it can be determined that the ECM is in fail-safe mode.
Result
Proceed to OK NG
Result:
NG
REPLACE ECM. Refer to REMOVAL [06/2018 - 08/2020]
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY - ECM)
- Disconnect the water inlet housing with water pump sub-assembly connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition C66-2 (SWP) - C88-50 (WPO) Always Below 1 Ω C66-2 (SWP) or C88-50 (WPO) - Body ground Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE WATER INLET HOUSING WITH WATER PUMP SUB-ASSEMBLY. Refer to REMOVAL [06/2018 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR