DTC P161A-87: Lost Communication with Alternator Missing Message [11/2021 - 03/2023]: Procedure
WARNING: This page is about a different car, the 2025 Lexus NX 250, 2024 Lexus NX 250, 2023 Lexus NX 250, and 2022 Lexus NX 250. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK CHARGING SYSTEM
Refer to ON-VEHICLE INSPECTION [11/2021 - ]
Result
Proceed to OK NG Result:
NG
REPAIR OR REPLACE CHARGING SYSTEM
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (ECM - GENERATOR ASSEMBLY)
- Disconnect the ECM connector.
- Disconnect the generator assembly connector.
- Disconnect the battery state sensor assembly connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition B50-62 (LIN) - B57-2 (LIN) Always Below 1 Ω B50-62 (LIN), B57-2 (LIN) or B45-2 (LIN) - 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
- CLEAR DTC
- Check for DTCs, and then write them down.
Powertrain > Engine > Trouble Codes
- Clear the DTCs.
Powertrain > Engine > Clear DTCs
- Turn the ignition switch off and wait 30 seconds.
Result
Proceed to NEXT
Result:
NEXT
See step 4
- Check for DTCs, and then write them down.
- CHECK DTC OUTPUT
- Start the engine.
- Allow the engine to idle for approximately 17 minutes or more.
- Check for DTCs.
Powertrain > Engine > Trouble Codes
Result
Result Proceed to Only DTC P161A-87 is output. A DTC P161A-87 and P162B-87 are output. B DTCs are not output. C
Result:
A
REPLACE GENERATOR ASSEMBLY. Refer to REMOVAL [11/2021 - ]
Result:
B
REPLACE ECM. Refer to REMOVAL [11/2021 - ]
Result:
C
CHECK FOR INTERMITTENT PROBLEMS. Refer to CHECK FOR INTERMITTENT PROBLEMS [11/2021 - ]