What Does B1560 Mean?
This code indicates the Body Control Module (BCM) has detected an open circuit in the door lock cylinder monitoring circuit. The door lock cylinder contains a switch or sensor that signals the BCM when the key is turned in the door lock. An open circuit means there is a complete break in electrical continuity, preventing the BCM from receiving the lock cylinder input signal.
Common Causes
40%
Broken, corroded, or disconnected wiring harness connector at the door lock cylinder switch
30%
Failed door lock cylinder switch internally open or damaged contact points
20%
Damaged wiring within the door jamb due to flexing from repeated door opening/closing
10%
Failed or corroded BCM internal circuitry or connector pins for door lock cylinder input
Diagnostic Steps
1
Step 1: Perform a visual inspection of the door lock cylinder switch and its connector, checking for obvious damage, corrosion, water intrusion, or disconnection. Wiggle the connector while monitoring for intermittent circuit closure.
2
Step 2: Using a digital multimeter, backprobe the door lock cylinder switch connector with key removed and measure resistance across the switch terminals. Expected reading should be open circuit (infinite ohms) at rest, and less than 5 ohms when key is turned in the cylinder.
3
Step 3: If switch tests good, disconnect the switch and measure continuity from the switch connector pins to the BCM connector pins using a wiring diagram. Check for infinite resistance indicating an open circuit in the harness, paying special attention to the door jamb area where wires flex.
4
Step 4: Inspect wiring in the door jamb boot/grommet area by carefully removing the boot and visually examining for broken or chafed wires. Flex the harness while measuring continuity to identify intermittent opens.
5
Step 5: If all wiring tests good, test the BCM input circuit by applying a jumper wire to simulate switch closure at the BCM connector (consult wiring diagram for correct pins). If BCM recognizes the input, replace the door lock cylinder switch; if not, suspect BCM fault.
6
Step 6: After repair, clear the code, cycle the door lock cylinder multiple times with the key, and verify the code does not return and the security/lock functions operate correctly.
Estimated Repair Cost
$100 - $450
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected an open circuit in the door lock cylinder monitoring circuit. The door lock cylinder contains a switch or sensor that signals the BCM when the key is turned in the door lock. An open circuit means there is a complete break in electrical ...
The most common cause of B1560 (Door Lock Cylinder Circuit Open) is: Broken, corroded, or disconnected wiring harness connector at the door lock cylinder switch
Typical repair costs for B1560 range from $100 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive. This affects the ability to lock/unlock the door using the key cylinder and may disable certain security features or anti-theft functions. Repair at your convenience, though compromised security features warrant timely attention.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1560 to identify the root cause.
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Quick Info
Category
Body
System
Body Control and Security System
Difficulty
Type
Manufacturer
Recommended Tools
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