Passenger Door Ajar Circuit Malfunction
What does B1012 mean?
The B1012 code means the vehicle's onboard diagnostic system has detected: Passenger Door Ajar Circuit Malfunction. This is a low severity code.
Common Symptoms
- Passenger door ajar warning always on
- Interior lights stay on with all doors closed
- Persistent door ajar chime
- Security system fails to arm
- Passenger door shows open on dash display
Probable Causes (Ranked by Likelihood)
- Failed passenger door jamb switch Very High
- Passenger door not latching completely High
- Damaged wiring in passenger door hinge area Moderate
- Body control module input error Low
Step-by-Step Diagnostic Procedure
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Check passenger door jamb switch operation
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Verify door latches fully when closed
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Inspect wiring through door hinge boot for breaks
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Scan BCM for door status inputs
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Test switch with multimeter for proper open/close resistance
Frequently Asked Questions
Where is the door jamb switch located?
The door jamb switch is typically a small plunger or pin switch mounted in the door pillar frame that gets depressed when the door is closed. On some vehicles, the latch assembly itself contains the switch.
Can I spray lubricant on the door jamb switch?
A small amount of electrical contact cleaner can help a sticky switch, but do not use heavy grease or oil that can attract dirt. If cleaning does not fix it, replacement is necessary.
Will this affect my auto-locking feature?
On some vehicles, the auto-lock feature that engages when driving will not activate if the system detects a door is ajar. This can be a safety concern.