DTC B2275: STSW Monitor Malfunction [10/2018 - ]: Procedure
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus UX 250h, 2023 Lexus UX 250h, 2022 Lexus UX 250h, 2021 Lexus UX 250h, and 2020 Lexus UX 250h. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR DTC
- Turn the power switch on (IG) and wait 25 seconds.
- Using the Techstream, check for certification ECU (smart key ECU assembly) DTCs.
Body Electrical > Power Source Control > Trouble Codes
OK
DTC B2285 is not output simultaneously.
Result
Proceed to OK NG
Result:
NG
GO TO DTC B2285. Refer to DTC B2285: Steering Lock Position Signal Circuit Malfunction [10/2018 - 07/2022] Refer to DTC B2285: Steering Lock Position Signal Circuit Malfunction [07/2022 - ]
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) - HYBRID VEHICLE CONTROL ECU)
- Disconnect the F44 certification ECU (smart key ECU assembly) connector.
- Disconnect the F59 hybrid vehicle control ECU connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition F44-27 (ST2) - F59-4 (ST2) Always Below 1 Ω F44-27 (ST2) or F59-4 (ST2) - Other terminals and body ground Always 10 kΩ or higher Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- CHECK CERTIFICATION ECU (SMART KEY ECU ASSEMBLY)
- Reconnect the F44 certification ECU (smart key ECU assembly) connector.
- Reconnect the F59 hybrid vehicle control ECU connector.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition F44-27 (ST2) - Body ground With the brake pedal depressed, the power switch is pressed and held → After approx. 3 sec. has elapsed, the power switch is released 8.5 V or higher → 1 V or less Result
Proceed to OK NG
Result:
OK
REPLACE HYBRID VEHICLE CONTROL ECU. Refer to REMOVAL [10/2018 - 07/2022] Refer to REMOVAL [07/2022 - ]
Result:
NG
REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY). Refer to REMOVAL [10/2018 - 07/2022] Refer to REMOVAL [07/2022 - ]