DTC B2788: IG2 Signal Malfunction [06/2018 - 09/2022]: Procedure
WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2024 Lexus ES 300h, 2023 Lexus ES 300h, 2022 Lexus ES 300h, 2021 Lexus ES 300h, and 2020 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK HARNESS AND CONNECTOR (POWER SOURCE)
- Disconnect the G51 steering lock ECU (steering lock actuator or upper bracket assembly) connector.
- Measure the voltage according to the value(s) in the table below.
*a Front view of wire harness connector
(to Steering Lock ECU (Steering Lock Actuator or Upper Bracket Assembly))Standard Voltage
Tester Connection Condition Specified Condition G51-6 (IG2) - Body ground Power switch on (IG) 11 to 14 V G51-6 (IG2) - Body ground Power switch off Below 1 V Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (GROUND)
- Measure the resistance according to the value(s) in the table below.
*a Front view of wire harness connector
(to Steering Lock ECU (Steering Lock Actuator or Upper Bracket Assembly))Standard Resistance
Tester Connection Condition Specified Condition G51-1 (GND) - Body ground Always Below 1 Ω Result
Proceed to OK NG
Result:
OK
REPLACE STEERING LOCK ECU (STEERING LOCK ACTUATOR OR UPPER BRACKET ASSEMBLY)
For Manual Tilt and Manual Telescopic Steering Column: Refer to DISASSEMBLY [06/2018 - 09/2022]
For Power Tilt and Power Telescopic Steering Column: Refer to DISASSEMBLY [06/2018 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
- Measure the resistance according to the value(s) in the table below.