DTC P26AC-11: Engine Coolant Bypass Valve "B" Circuit Short to Ground; DTC P26AC-15: Engine Coolant Bypass Valve "B" Circuit Short to Battery or Open [08/2020 - 08/2021]: Procedure
WARNING: This page is about a different car, the 2024 Lexus ES 250, 2023 Lexus ES 250, 2022 Lexus ES 250, and 2021 Lexus ES 250. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK TERMINAL VOLTAGE (POWER SOURCE OF FLOW SHUTTING VALVE (FOR ATF CONTROL))
*a Front view of wire harness connector
(to Flow Shutting Valve (for ATF Control) (No. 1 Water By-pass Hose))- Disconnect the flow shutting valve (for ATF control) (No. 1 water by-pass hose) connector.
- Turn the engine switch on (IG).
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition F8-2 (+FSV) - Body ground Engine switch on (IG) 11 to 14 V Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI-MAIN NO. 1 RELAY - FLOW SHUTTING VALVE (FOR ATF CONTROL))
Result:
OK
See step 2
- INSPECT FLOW SHUTTING VALVE (FOR ATF CONTROL) (NO. 1 WATER BY-PASS HOSE)
- Inspect the flow shutting valve (for ATF control) (No. 1 water by-pass hose).
Refer to INSPECTION [08/2020 - ]
Result
Proceed to OK NG
Result:
NG
REPLACE FLOW SHUTTING VALVE (FOR ATF CONTROL) (NO. 1 WATER BY-PASS HOSE). Refer to REMOVAL [08/2020 - 08/2021]
Result:
OK
See step 3
- Inspect the flow shutting valve (for ATF control) (No. 1 water by-pass hose).
- CHECK HARNESS AND CONNECTOR (FLOW SHUTTING VALVE (FOR ATF CONTROL) - ECM)
- Disconnect the flow shutting valve (for ATF control) (No. 1 water by-pass hose) connector.
- Disconnect the ECM connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition F8-1 (-FSV) - C77-41 (WSV2) Always Below 1 Ω F8-1 (-FSV) or C77-41 (WSV2) - Body ground and other terminals Always 10 kΩ or higher Result
Proceed to OK NG
Result:
OK
REPLACE ECM. Refer to REMOVAL [08/2020 - 08/2021]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR