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 DTC B2721

DTC B2721


id0902j0833300

DTC B2721

Trunk lid/liftgate ajar output short to ground

DETECTION CONDITION

Short to GND in wiring harness between BCM and trunk compartment light switch (4SD) or cargo compartment light switch (5HB, WGN)

POSSIBLE CAUSE

• Short to GND in wiring harness between BCM terminal 2F and trunk compartment light switch/cargo compartment light switch terminal B
• Trunk compartment light switch malfunction
• Cargo compartment light switch malfunction
• BCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT TRUNK COMPARTMENT LIGHT SWITCH CONNECTOR
• Disconnect the trunk compartment light switch connector.
• Inspect the trunk/cargo compartment light switch connector terminals for poor connection (such as damaged/pulled-out pins, and corrosion).
• Is there any malfunction?
Yes
Repair or replace the terminal, then go to Step 5.
No
Go to the next step.
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?
Yes
Repair or replace the terminal, then go to Step 5.
No
Go to the next step.
3
INSPECT TRUNK COMPARTMENT LIGHT SWITCH SIGNAL CIRCUIT FOR SHORT TO GND
• Inspect for continuity between BCM terminal 2F (wiring harness-side) and body GND.
• Is there continuity?
Yes
Repair or replace the wiring harness for a possible short to GND, then go to Step 5.
No
Go to the next step.
4
INSPECT TRUNK/CARGO COMPARTMENT LIGHT SWITCH
• Inspect the trunk/cargo compartment light switch.
• Is there any malfunction?
Yes
Replace the trunk/cargo compartment light switch, then go to the next step.
No
Go to the next step.
5
VERIFY TROUBLESHOOTING COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the BCM memory using the WDS or equivalent.
• Is the same DTC present?
Yes
Replace the BCM.
No
DTC troubleshooting completed.