B1393 – Power Door Memory Lock Relay Circuit Open

The ODBII code B1393 indicates that there is an open circuit in the power door memory lock relay, which affects the operation of the door locking system.

The severity of ODBII code B1393 is moderate.

Common Causes For: B1392 Power Door Memory Lock Relay Circuit Failure

• Faulty power door memory lock relay
• Open or shorted wiring in the relay circuit
• Corroded or damaged connectors
• Faulty door lock control module
• Blown fuse related to the door lock system
• Malfunctioning body control module (BCM)

Common misdiagnosis for B1393 Power Door Memory Lock Relay Circuit Open

• Faulty door lock actuator
• Malfunctioning body control module (BCM)
• Wiring issues or shorts in the door harness
• Defective power door lock switch
• Battery or charging system problems
• Incorrectly programmed key fob or remote
• Issues with the vehicle’s security system

Common Troubleshooting Steps

The OBD-II code B1393 indicates a problem with the power door memory lock relay circuit, specifically that the circuit is open. This can affect the operation of the power door locks and may be related to the vehicle’s security system. Here are some common troubleshooting steps to diagnose and resolve the issue:

• Check the Vehicle’s Manual: Refer to the vehicle’s service manual for specific information about the power door memory lock relay circuit and its components.
• Visual Inspection: Inspect the wiring and connectors associated with the power door lock system. Look for any signs of damage, corrosion, or loose connections.
• Check the relay itself for any physical damage.
• Test the Relay: Locate the power door memory lock relay in the fuse box or relay panel.
• Use a multimeter to test the relay for continuity. If the relay is faulty, replace it with a new one.
• Check Fuses: Inspect the fuses related to the power door locks and the relay circuit. Replace any blown fuses.
• Inspect the Door Lock Actuators: Check the door lock actuators for proper operation. If an actuator is malfunctioning, it may cause issues with the relay circuit.
• Test the Circuit: Use a multimeter to check for voltage at the relay terminals when the door lock switch is activated. If there is no voltage, trace the wiring back to the switch and check for continuity.
• Check for ground connections as well, ensuring that the relay has a proper ground.
• Scan for Additional Codes: Use an OBD-II scanner to check for any additional trouble codes that may provide more context to the issue.
• Inspect the Body Control Module (BCM): The BCM controls the power door locks. If all other components check out, the BCM may be faulty. Testing or reprogramming the BCM may be necessary.
• Check for Short Circuits: Inspect the wiring harness for any signs of short circuits or pinched wires that could cause an open circuit.
• Clear the Code and Test Drive: After performing repairs, clear the trouble code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns.1
• Consult a Professional: If the issue persists after performing these steps, it may be best to consult a professional mechanic or technician who has experience with your specific vehicle make and model. By following these troubleshooting steps, you should be able to identify and resolve the issue related to the B1393 code.