DTC P1753-87: Lost Communication with Gear Shift Control Module "B" (Local-CAN) Missing Message [09/2023 - ]: Procedure
WARNING: This page is about a different car, the 2024 Lexus TX 500h. However, it is still accessible from the selected car via links, so may be relevant.
- CHECK DTC OUTPUT (HYBRID CONTROL)
Pre-procedure1
- Turn the ignition switch to ON.
- Check if DTCs are output.
Powertrain > Hybrid Control > Trouble Codes
Result
Result Proceed to P1753-87 and DTCs in the table below are output A None of the above conditions are met B Relevant DTC U0291-00 Lost Communication with Gear Shift Control Module "B" (System 2) Missing Message U0291-87 Lost Communication with Gear Shift Control Module "B" Missing Message
Post-procedure1
- Turn the ignition switch off.
Result:
A
REPLACE SHIFT ACTUATOR ECU (SHIFT CONTROL ACTUATOR ASSEMBLY). Refer to REMOVAL [09/2023 - ]
Result:
B
See step 2
- CHECK HARNESS AND CONNECTOR (SHIFT CONTROL ECU - SHIFT ACTUATOR ECU)
Pre-procedure1
- Disconnect the D25 shift control ECU (transmission floor shift assembly) connector.
- Disconnect the C64 shift actuator ECU (shift control actuator assembly) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result D25-24 (CA4H) - C64-4 (CA4H) Always Below 1 Ω Ω D25-10 (CA4L) - C64-3 (CA4L) Always Below 1 Ω Ω D25-24 (CA4H) or C64-4 (CA4H) - Body ground and other terminals Always 10 kΩ or higher kΩ D25-10 (CA4L) or C64-3 (CA4L) - Body ground and other terminals Always 10 kΩ or higher kΩ Result
Proceed to OK NG
Post-procedure1
- Connect the shift actuator ECU (shift control actuator assembly) connector.
- Connect the shift control ECU (transmission floor shift assembly) connector.
Result:
NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
Result:
OK
See step 3
- CHECK SHIFT ACTUATOR ECU (SHIFT CONTROL ACTUATOR ASSEMBLY)
Pre-procedure1
- Disconnect the D25 shift control ECU (transmission floor shift assembly) connector.
- Measure the resistance according to the value(s) in the table below.
Standard Resistance
Tester Connection Condition Specified Condition Result D25-24 (CA4H) - D25-10 (CA4L) Ignition switch off 108 to 132 Ω Ω Result
Proceed to OK NG
Post-procedure1
- Connect the shift control ECU (transmission floor shift assembly) connector.
Result:
OK
REPLACE SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY). Refer to REMOVAL [09/2023 - ]
Result:
NG
REPLACE SHIFT ACTUATOR ECU (SHIFT CONTROL ACTUATOR ASSEMBLY). Refer to REMOVAL [09/2023 - ]