B1214

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1214: Short to B+ in Door System Communication Bus Malfunction

DTC B1214 - Short to B+ in Door System Communication Bus Malfunction

DTC B1215 - Short to GND in Door System Communication Bus Malfunction

DESCRIPTION
- When a +B short circuit or body ground short circuit is detected on the door system communication bus (BEAN), BEAN is disabled and a DTC is output.





WIRING DIAGRAM





INSPECTION PROCEDURE

PROCEDURE

1. CHECK DIAGNOSTIC TROUBLE CODE (A ECU)
(a) Disconnect the A ECU connector and check for DTCs B1214 and B1215.





OK:
Neither DTC B1214 nor DTC B1215 is output.
NOTE: Reconnect the connector before starting the next check.
HINT:
- The A ECU in the door system bus represents the transponder key ECU.
- If the result is as specified, the disconnected A ECU (Transponder key ECU) is malfunctioning.

OK -- REPLACE A ECU
NG -- Continue to next step.
2. CHECK DIAGNOSTIC TROUBLE CODE (B ECU)
(a) Disconnect the A ECU and B ECU connectors and check for DTCs B1214 and B1215.





OK:
Neither DTC B1214 nor DTC B1215 is output.
NOTE: Disconnect the connectors one by one. Reconnect the connectors before starting the next check.
HINT:
- Remove the B ECUs in the following order:

- Main body ECU
- Power window control switch rear LH
- Power window control switch rear RH
- Power window control switch front RH
- Power window master switch
- Remote control mirror ECU LH (*2)
- Remote control mirror ECU RH (*2)
- Power back door ECU (*1)
- Power seat ECU (Driver side seat) (*1)
- AFS ECU (*2)
- Tilt and telescopic ECU (*4)
- Tire pressure warning ECU (*3)

- 1: with driving position memory
- 2: with adaptive front-lighting system
- 3: with tire pressure warning system
- 4: with power tilt and power telescopic
- If the result is as specified, the disconnected B ECU (one of the ECUs from the above list) or the wire harness between the A ECU and B ECU is malfunctioning.
- After the DTC is cleared, proceed to the next step.

NG -- CHECK DIAGNOSTIC TROUBLE CODE (C ECU)
OK -- Continue to next step.
3. CHECK WIRE HARNESS BETWEEN A ECU AND B ECU
(a) Disconnect the B ECU connector and check for DTCs B1214 and B1215.





OK:
Neither DTC B1214 nor DTC B1215 is output.
NOTE: Reconnect the connector before starting the next check.
HINT:
- If the result is as specified, the wire harness between the A ECU and B ECU is functioning normally but the disconnected B ECU is malfunctioning.

NG -- REPAIR OR REPLACE WIRE HARNESS BETWEEN A ECU AND B ECU
OK -- REPLACE B ECU
4. CHECK DIAGNOSTIC TROUBLE CODE (C ECU)
(a) Disconnect the B ECU and C ECU connectors and check for DTCs B1214 and B1215.





OK:
Neither DTC B1214 nor DTC B1215 is output.
NOTE: Disconnect the connectors one by one. Reconnect the connectors before starting the next check.
HINT:
- The C ECU in the door system bus represents the windshield wiper switch.
- If the result is as specified, the disconnected C ECU (Power window master switch (*1, *2), tilt and telescopic ECU (*1), tire pressure warning ECU (*2)) or the wire harness between the B ECU and C ECU is malfunctioning.

- *1: without tire pressure warning ECU
- *2: without tilt and telescopic ECU

NG -- CHECK WIRE HARNESS BETWEEN NETWORK GATEWAY ECU AND A ECU OR C ECU
OK -- Continue to next step.
5. CHECK WIRE HARNESS BETWEEN B ECU AND C ECU
(a) Disconnect the C ECU connector and check for DTCs B1214 and B1215.





OK:
Neither DTC B1214 nor DTC B1215 is output.
NOTE: Reconnect the connector before starting the next check.
HINT: If the result is as specified, the wire harness between the B ECU and C ECU is functioning normally but the disconnected C ECU is malfunctioning.

NG -- REPAIR OR REPLACE WIRE HARNESS BETWEEN B ECU AND C ECU
OK -- REPLACE C ECU
6. CHECK WIRE HARNESS BETWEEN NETWORK GATEWAY ECU AND A ECU OR C ECU
(a) Check for a short-circuit in B+ or body ground.





(1) Disconnect the A ECU, C ECU and multiplex network gateway ECU connectors.
(2) Measure the voltage and resistance of the wire harness side connectors.
Standard voltage:






Standard resistance:





HINT:
- The A ECU in the door system bus represents the Transponder key ECU.
- The C ECU in the door system bus represents the power window master switch (*1, *2), tilt and telescopic ECU (*1), tire pressure warning ECU (*2).

- *1: without tire pressure warning ECU
- *2: without tilt and telescopic ECU

NG -- REPAIR OR REPLACE WIRE HARNESS BETWEEN NETWORK GATEWAY ECU AND A ECU OR C ECU
OK -- REPLACE MULTIPLEX NETWORK GATEWAY ECU