DTC    B1242    Wireless Door Lock Tuner Circuit Malfunction

for Preparation Click here


DESCRIPTION

The door control receiver is used to receive electrical waves relating to the entry functions of the entry and start system. The certification ECU decodes the requested entry and start system operation by identifying a key code based on the electric waves received via the door control receiver. The door control receiver receives a signal from the door control transmitter and sends signals to the main body ECU through the certification ECU. The certification ECU then sends a command, according to the requested operation, to each ECU (ex. if door lock operation is requested, the certification ECU sends a door lock command to the main body ECU).

DTC No.
DTC Detection Condition
Trouble Area
B1242
  1. Short in RDA3 or RSSI to ground between the certification ECU and the door control receiver.
  2. Short in RDA3 or RSSI to ground when RC0 (5 V) output from the ECU is off.
  1. Door control receiver
  2. Wire harness or connector
  3. Certification ECU

WIRING DIAGRAM


B211542E01


INSPECTION PROCEDURE

NOTICE:
  1. When replacing or inspecting the door control receiver and wire harness, do not change the position or length of the wire harness. If the wire harness is too close to the door control receiver, entry and wireless function performance may be affected.
  2. Before performing the inspection, check that there are no problems related to the CAN communication system and LIN communication system.

1.CHECK HARNESS AND CONNECTOR (DOOR CONTROL RECEIVER - CERTIFICATION ECU AND BODY GROUND)


  1. Disconnect the D34 and D35 certification ECU connector.


    B211546E01


    Text in Illustration 
    *1
    		Front view of wire harness connector
    (to Certification ECU)
    		*2
    		Front view of wire harness connector
    (to Door Control Receiver)

  1. Disconnect the G32 door control receiver connector.

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

    Standard Resistance:
    Tester Connection
    		Condition
    		Specified Condition
    D35-16 (RSSI) - G32-2 (RSSI)
    		Always
    		Below 1 Ω
    D35-15 (RDA) - G32-5 (DATA)
    		Always
    		Below 1 Ω
    D35-5 (RCO) - G32-4 (+5)
    		Always
    		Below 1 Ω
    D34-15 (E) - Body ground
    		Always
    		Below 1 Ω
    G32-1 (GND) - Body ground
    		Always
    		Below 1 Ω
    D35-16 (RSSI) or G32-2 (RSSI) - Body ground
    		Always
    		10 kΩ or higher
    D35-15 (RDA) or G32-5 (DATA) - Body ground
    		Always
    		10 kΩ or higher
    D35-5 (RCO) or G32-4 (+5) - Body ground
    		Always
    		10 kΩ or higher



NG
REPAIR OR REPLACE HARNESS OR CONNECTOR
OK


2.INSPECT CERTIFICATION ECU


  1. Reconnect the D34 and D35 certification ECU connector.


    B214940E01


    Text in illustration 
    *1
    		Component with harness connected
    (Certification ECU)

  1. Measure the voltage according to the value(s) in the table below.

    Standard Voltage:
    Tester Connection
    		Switch Condition
    		Specified Condition
    D35-5 (RC0) - D34-15 (E)
    		Engine switch off, all doors closed and transmitter switch pressed
    		Pulse generation → 4.5 to 5.5 V



NG
REPLACE CERTIFICATION ECU
OK


3.REPLACE DOOR CONTROL RECEIVER

  1. Temporarily replace the door control receiver with a new one (Click here).


NEXT


4.CHECK FOR DTC

  1. Clear the DTC (Click here).

  1. Recheck for DTCs.

    OK:
    DTC B1242 is not output.



NG
REPLACE CERTIFICATION ECU
OK

END (DOOR CONTROL RECEIVER IS DEFECTIVE)