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

* DTC B1214 is detected when the door system communication circuit and +B battery are shorted. DTC B1215 is detected when the communication circuit and body ground are shorted. When this condition is detected, the door system communication bus (BEAN) will be disabled and some diagnosis codes will be output.





HINT
*1: w/ Smart key system

*2: w/ Driving position memory

*3: w/ Engine immobilizer w/ alarm

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

HINT
* The A ECU represents the A/C ECU.
* If any of the stated DTCs are not output, the disconnected A ECU (A/C ECU) is malfunctioning.

NG -- CHECK DIAGNOSTIC TROUBLE CODE (B ECU)

OK -- REPLACE A ECU

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:
* Power source ECU
* Certification ECU
* Combination switch ECU
* Body ECU
* Option connector
* Front controller
* Rain sensor
* Front controller
* Power seat ECU
* Memory mirror ECU (LH)
* Memory mirror ECU (RH)
* If any of the stated DTCs are not output, 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) Connect the A ECU connector.

(b) Disconnect the 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
If any of the stated DTCs are not output, 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) Connect the A ECU connector.

(b) 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 represents the combination meter ECU.
* If any of the stated DTCs are not output, the disconnected C ECU (combination meter ECU) or the wire harness between the B ECU and C ECU is malfunctioning.

NG -- CHECK WIRE HARNESS BETWEEN GATEWAY ECU AND A ECU OR C ECU
OK -- Continue to next step.

5. CHECK WIRE HARNESS BETWEEN B ECU AND C ECU

(a) Connect the B ECU connector.

(b) Disconnect the C ECU connector 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
If any of the stated DTCs are not output, 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 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 gateway ECU connectors.

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

Voltage:





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

Resistance:





HINT
* The A ECU represents the A/C ECU.
* The C ECU represents the combination meter ECU.

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

OK -- REPLACE MULTIPLEX NETWORK GATEWAY ECU