What Does B1324 Mean?
B1324 indicates the Body Control Module (BCM) has detected an open circuit in the door ajar warning lamp circuit. This means the electrical pathway from the BCM to the door ajar indicator lamp on the instrument cluster is incomplete or broken. The BCM is unable to illuminate the door ajar warning light when commanded, preventing the driver from being notified when a door is not properly closed.
Common Causes
35%
Failed or burned out door ajar warning lamp bulb in instrument cluster
30%
Open circuit in wiring harness between BCM and instrument cluster due to broken wire or poor connection
20%
Faulty instrument cluster internal circuit board or lamp driver
10%
Corroded or damaged connector terminals at BCM or instrument cluster
5%
Failed Body Control Module lamp output driver circuit
Diagnostic Steps
1
Step 1: Visually inspect the instrument cluster for non-functioning door ajar lamp. Turn ignition on and manually trigger door switches to verify lamp does not illuminate when commanded.
2
Step 2: Access instrument cluster connector and use a multimeter to check for voltage at the door ajar lamp circuit wire when door switch is triggered. BCM should supply voltage (typically 12V) when door is opened.
3
Step 3: If no voltage present at cluster connector, backprobe the BCM connector door ajar lamp output circuit with multimeter while triggering door switches. This isolates fault to BCM side or cluster side of circuit.
4
Step 4: Inspect wiring harness between BCM and instrument cluster for damaged, pinched, or broken wires. Check all connector terminals for corrosion, bent pins, or poor contact. Perform continuity test on lamp circuit wire from BCM to cluster.
5
Step 5: If voltage is present at cluster connector but lamp does not illuminate, remove instrument cluster and test lamp bulb/LED directly with external power source, or replace instrument cluster if internal circuit fault is confirmed.
6
Step 6: Clear codes and verify repair by commanding door ajar lamp illumination through scan tool bidirectional controls (if available) or by opening/closing doors while monitoring system operation.
Estimated Repair Cost
$75 - $450
Parts + labor, varies by vehicle and location
B1324 indicates the Body Control Module (BCM) has detected an open circuit in the door ajar warning lamp circuit. This means the electrical pathway from the BCM to the door ajar indicator lamp on the instrument cluster is incomplete or broken. The BCM is unable to illuminate the door ajar warning li...
The most common cause of B1324 (Door Ajar Lamp Circuit Open) is: Failed or burned out door ajar warning lamp bulb in instrument cluster
Typical repair costs for B1324 range from $75 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to continue driving. The vehicle remains fully operational, but the driver will not receive visual warning if a door is not properly closed, which could result in a door opening while driving. Repair at earliest convenience to maintain awareness of door status.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1324 to identify the root cause.
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Quick Info
Category
Body
System
Body Control and Warning Systems
Difficulty
Type
Manufacturer
Recommended Tools
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