DTC B1242-96: Wireless Door Lock Tuner Component Internal Failure [11/2023 - ]: Procedure

Pre-procedure1

1. Disconnect the M51 electrical key and tire pressure monitoring system receiver assembly connector.

   Procedure1

2. Measure the voltage and resistance and check for pulses according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   *a

   Component with harness connected (Certification ECU (Smart Key ECU Assembly))

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   -

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   H138-29 (E) - Body ground	Always	Below 1 Ω

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   M106-11 (RDAM) - H138-29 (E)	Always	11 to 14 V
   M106-21 (RCO) - H138-29 (E)	Always	Below 1 V → 4.5 to 5.5 V pulse generation at regular intervals

   Result

   Proceed to
   OK
   NG

   Post-procedure1

3. None

Result: 

OK 

REPLACE ELECTRICAL KEY AND TIRE PRESSURE MONITORING SYSTEM RECEIVER ASSEMBLY 

Refer to REMOVAL [11/2023 - ]

Result: 

NG 

See step  2

Pre-procedure1

1. Disconnect the M106 certification ECU (smart key ECU assembly) connector.

   Procedure1

2. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   M51-2 (DATA) - M106-11 (RDAM)	Always	Below 1 Ω
   M51-8 (+5) - M106-21 (RCO)	Always	Below 1 Ω
   M51-12 (GND) - Body ground	Always	Below 1 Ω
   M51-2 (DATA) or M106-11 (RDAM) - Other terminals and body ground	Always	10 kΩ or higher
   M51-8 (+5) or M106-21 (RCO) - Other terminals and body ground	Always	10 kΩ or higher

   Result

   Proceed to
   OK
   NG

   Post-procedure1

3. None

Result: 

OK 

REPLACE CERTIFICATION ECU (SMART KEY ECU ASSEMBLY) 

Refer to REMOVAL [11/2023 - ]

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR