B1214

MULTIPLEX COMMUNICATION: MULTIPLEX COMMUNICATION SYSTEM: B1214, B1215: Short to B+ in Door System Communication Bus Malfunction
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.

NOTICE:
Reconnect the connector before starting the next check.

HINT
* The A ECU in the door system bus represents the main body ECU RH.
* If the result is as specified, the disconnected A ECU (main body ECU RH) 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.

NOTICE:
Disconnect the connectors one by one. Reconnect the connectors before starting the next check.

HINT
* Remove the B ECUs in the following order:
* Tilt and telescopic ECU
* Power window master switch
* Certification ECU
* Power source control ECU
* Position control ECU and switch (Front LH seat)
* Main body ECU LH
* Outer mirror control ECU (RH)
* Outer mirror control ECU (LH)
* Front controller
* Overhead J/B
* Rain sensor
* Sliding roof control ECU
* 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.

NOTICE:
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.

NOTICE:
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 (windshield wiper switch) or the wire harness between the B ECU and C ECU is malfunctioning.

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.

NOTICE:
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 main body ECU RH.
* The C ECU in the door system bus represents the windshield wiper switch.

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

OK -- REPLACE MULTIPLEX NETWORK GATEWAY ECU