B1311: Power Door Unlock Circuit Open
Diagnostic trouble code B1311 indicates an open circuit in the power door unlock system. This means the body control module (BCM) or door module has detected a break or loss of continuity in the wiring that supplies power to the door lock actuators. When the BCM attempts to send the unlock signal, it does not detect the expected current flow to the door actuators, preventing the power locks from functioning.
1. Commonly Affected Makes
2. Most Common Causes
- Blown or open fuse in the door lock circuit
- Broken or interrupted wiring in the unlock circuit
- Corroded, bent, or pushed-out electrical connector at the door actuator
- Defective door lock actuator (open internal coil)
- Internal failure of the body control module (BCM)
3. Symptoms You Will Notice
- Power door locks fail to unlock using the switch or remote
- One or more doors may not unlock electrically while others work
4. Step-by-Step Diagnosis
Check the door lock system fuse and replace if blown
Inspect wiring and connectors for damage, corrosion, or poor contact
Test continuity of the unlock circuit between BCM and door actuator
Verify actuator operation by applying power and ground directly
If all else is good, suspect a faulty BCM and perform module diagnostics
5. Frequently Asked Questions
Is it safe to drive?▼
Yes, the vehicle is safe to drive. The main issue is that the power door locks may not unlock electrically, but you can still manually unlock the doors. The severity is low.
How much does it cost to fix?▼
Repair costs vary widely. A simple fuse replacement can cost under $20, while a faulty actuator may run $150–$300 including labor. BCM replacement can exceed $500.