DTC B1242: Wireless Door Lock Tuner Circuit Malfunction: Procedure

1. Disconnect the E36 certification ECU connector and M14 door control receiver connector.
   Fig 1: Identifying E36 Certification ECU And M14 Door Control Receiver Connectors

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
   1. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection	Condition	Specified Condition
      E36-39 (RSSI) - M14-5 (RSSI)	Always	Below 1 Ω
      E36-38 (RDA) - M14-3 (DATA)	Always	Below 1 Ω
      E36-39 (RSSI) - E36-38 (RDA)	Always	10 kΩ or higher
      E36-39 (RSSI) - Body ground	Always	10 kΩ or higher
      E36-38 (RDA) - Body ground	Always	10 kΩ or higher

NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

OK: Go to next step 

1. Reconnect the E36 ECU connector.
   Fig 2: Identifying E36 ECU Connector Terminal

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   E36-39 (RSSI) - E36-17 (E)	Engine switch off, all doors closed, the electrical key is not in the actuation area	Below 1 V
   	Engine switch off, all doors closed, the electrical key is in the actuation area	4.6 to 5.4 V
   E36-38 (RDA) - E36-17 (E)	Engine switch off, all doors closed and transmitter switch not pressed	11 to 14 V pulse generation at regular intervals
   	Engine switch off, all doors closed and transmitter switch pressed	Pulse generation

NG → See step   5 

OK: Go to next step 

1. Replace the door control receiver with a known good one. Refer to REMOVAL .

NEXT: Go to next step 

1. Clear the DTCs. Refer to DTC CHECK / CLEAR .
2. Check if the same DTC is detected.

   Result

   Result	Proceed to
   DTC is not output	A
   DTC is output	B

B → See step   5 

A → END (DOOR CONTROL RECEIVER IS DEFECTIVE)