Mazda CX-7 2007 Workshop Manual page 1379

DTC B2218[BCM]
DTC B2218 Door lock switch circuit short to ground
DETECTION Short to GND in wiring harness between BCM and door lock switches
CONDITION
• Short to GND in wiring harness between BCM terminal 5M and door lock switch (driver-side) terminal
C
• Short to GND in wiring harness between BCM terminal 5N and door lock switch (passenger-side)
POSSIBLE
CAUSE terminal C
• Door lock switches malfunction
• BCM malfunction
C
LOCK UNLOCK
D
DOOR LOCK SWITCH
(PASSENGER-SIDE)
DOOR LOCK SWITCH WIRING
HARNESS-SIDE CONNECTOR
Diagnostic procedure
STEP
1 INSPECT DOOR LOCK SWITCH
CONNECTOR
• Disconnect the door lock switch connector.
• Inspect the door lock switch connector
terminals for poor connection (such as
damaged/pulled-out pins, and corrosion).
• Is there any malfunction?
2 INSPECT BCM CONNECTOR
• Disconnect the BCM connector.
• Inspect the BCM connector terminals for
poor connection (such as damaged/pulled-
out pins, and corrosion).
• Is there any malfunction?
3 INSPECT DOOR LOCK SWITCH SIGNAL
CIRCUIT FOR SHORT TO GND
• Inspect for continuity between BCM terminal
5M, 5N (wiring harness-side) and body GND.
• Is there continuity?
4 INSPECT DOOR LOCK SWITCH
• Inspect the door lock switch.
(See 09-14-8 DOOR LOCK SWITCH
INSPECTION.)
• Is there any malfunction?
ON-BOARD DIAGNOSTIC [BCM]
C
LOCK
D
DOOR LOCK SWITCH
(DRIVER-SIDE)
D C
B A
INSPECTION
UNLOCK
BCM WIRING HARNESS-SIDE
CONNECTOR
5AB 5Y 5V 5S 5P 5M
5AC 5Z 5W 5T 5Q 5N
5AD 5AA 5X 5U 5R 5O
Yes Repair or replace the terminal, then go to Step 5.
No Go to the next step.
Yes Repair or replace the terminal, then go to Step 5.
No Go to the next step.
Yes Repair or replace the wiring harness for a possible short to
GND, then go to Step 5.
No Go to the next step.
Yes Replace the door lock switch, then go to the next step.
(See 09-14-8 DOOR LOCK SWITCH REMOVAL/
INSTALLATION.)
No Go to the next step.
id0902f5839700
BCM
5N
5M
5J 5G 5D 5A
5K 5H 5E 5B
5L 5I 5F 5C
ACTION
09-02F–17
09-02F