Power Back Door ECU Communication Stop Mode [11/2021 - ]: Procedure
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2025 Lexus NX 350, 2025 Lexus NX 250, 2024 Lexus NX 350, 2024 Lexus NX 250, and 2023 Lexus NX 350. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK FOR OPEN IN CAN BUS LINES (MULTIPLEX NETWORK DOOR ECU BRANCH LINE)
- Disconnect the cable from the negative (-) battery terminal.
- Disconnect the P21 multiplex network door ECU connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition P21-10 (CANP) - P21-20 (CANN) Cable disconnected from negative (-) battery terminal 54 to 69 Ω Result
Proceed to OK NG
Result:
NG
REPAIR OR REPLACE CAN BRANCH LINES OR CONNECTOR (MULTIPLEX NETWORK DOOR ECU)
Result:
OK
See step 2
- CHECK HARNESS AND CONNECTOR (POWER SOURCE CIRCUIT)
- Disconnect the P19 multiplex network door ECU connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition P19-4 (GND) - Body ground Cable disconnected from negative (-) battery terminal Below 1 Ω - Disconnect the P18 multiplex network door ECU connector.
- Reconnect the cable to the negative (-) battery terminal.
- Measure the voltage according to the value(s) in the table below.
Standard Voltage
Tester Connection Condition Specified Condition P21-7 (ECUB) - Body ground Always 11 to 14 V P18-5 (B) - Body ground Always 11 to 14 V P21-9 (IG) - Body ground Ignition switch ON 11 to 14 V Result
Proceed to OK NG
Result:
OK
REPLACE MULTIPLEX NETWORK DOOR ECU. Refer to REMOVAL [11/2021 - ]
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)