Passenger Door Ajar Circuit Malfunction
What does B1302 mean?
The B1302 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 indicator stays on
- Interior lights remain on
- Door open chime sounds continuously
- Vehicle security system affected
- Remote start disabled on some models
Probable Causes (Ranked by Likelihood)
- Stuck or faulty passenger door ajar switch Very High
- Passenger door not latching completely High
- Corroded switch contacts in door latch Moderate
- Damaged wiring in passenger door jamb Moderate
- BCM misreading door signal Low
Step-by-Step Diagnostic Procedure
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Verify passenger door is closing and latching fully
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Monitor door ajar switch status with scan tool
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Inspect door latch mechanism for proper operation
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Apply contact cleaner to latch mechanism
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Check door jamb wiring boot for damaged wires
Frequently Asked Questions
Is the door ajar switch separate from the door latch?
On most modern vehicles, the door ajar switch is integrated into the door latch assembly. Replacing it typically means replacing the entire latch mechanism.
Can a sagging door cause this code?
Yes. If door hinges wear and the door sags, it may not engage the latch fully, causing the door ajar switch to remain in the open position.
Will this affect my alarm system?
Yes. The vehicle security system relies on door ajar signals. A stuck switch can prevent the alarm from arming or cause false alarm triggers.