DTC P1752-31: Fail Safe Signal (Gear Shift Control Module "B" to "A") No Signal [12/2022 - ]: Procedure

Pre-procedure1

• Connect an oscilloscope between the shift control ECU (transmission floor shift assembly) terminals specified in the table below.
• Turn the ignition switch to ON.

• Measure the waveform.

  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

  *a	Component with harness connected (shift control ECU (transmission floor shift assembly))
  *b	Waveform (Fail Safe Signal)

  Tester Connection	Condition	Equipment Setting
  K53-14 (FS) - K53-9 (E1)	Ignition switch ON	10 V/DIV., 20 ms./DIV.

  HINT: 

  Perform the inspection with the connector of the shift control ECU and shift actuator ECU connected.

  Result

  Proceed to
  OK
  NG

Post-procedure1

• Turn the ignition switch off.

Result: 

OK 

REPLACE SHIFT CONTROL ECU (TRANSMISSION FLOOR SHIFT ASSEMBLY). Refer to  REMOVAL [12/2022 - ] 

Result: 

NG 

See step  2

Pre-procedure1

• Disconnect the K53 shift control ECU (transmission floor shift assembly) connector.
• Disconnect the C50 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
  K53-14 (FS) - C50-6 (FS)	Always	Below 1 Ω	Ω
  K53-14 (FS) or C50-6 (FS) - 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: 

OK 

REPLACE SHIFT ACTUATOR ECU (SHIFT CONTROL ACTUATOR ASSSEMBLY). Refer to  REMOVAL [12/2022 - ] 

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR