What Does B1269 Mean?
This code indicates the body control module (BCM) has detected an open circuit in the potentiometer feedback circuit of the servo motor that controls the defrost mode door in the HVAC system. The potentiometer provides position feedback to the BCM, and an open circuit means the BCM cannot verify the actuator's position. This prevents proper operation of the defrost airflow distribution.
Common Causes
45%
Failed defrost door actuator with internal potentiometer failure or broken wiring harness
30%
Broken or corroded wiring connections at the actuator connector
15%
Damaged wiring between BCM and defrost actuator (chafed, cut, or broken wire)
10%
Failed body control module with internal circuit board damage
Diagnostic Steps
1
Step 1: Locate and visually inspect the defrost door actuator (typically behind or under dashboard near defroster vents). Check connector for corrosion, pushed-out pins, moisture, or damage. Wiggle connector while observing for intermittent connection.
2
Step 2: Using a digital multimeter, backprobe the potentiometer signal wire at the actuator connector (typically 5V reference). Measure voltage with key on, engine off. Expected reading: 0.5-4.5V depending on door position. If no voltage present, suspect open circuit in wiring.
3
Step 3: Disconnect actuator connector and measure resistance across potentiometer terminals (usually 3-wire connector with power, ground, and signal). Manually rotate actuator gear and verify resistance changes smoothly between 1-5k ohms. No reading or infinite resistance confirms failed potentiometer.
4
Step 4: If actuator tests good, check continuity of all three wires from actuator connector back to BCM connector using wiring diagram. Repair any open circuits found in harness.
5
Step 5: After repairs, clear code and operate HVAC system through all modes including defrost. Monitor live data on scan tool to verify potentiometer voltage changes smoothly through full range of motion. Confirm defrost airflow functions properly.
Estimated Repair Cost
$150 - $450
Parts + labor, varies by vehicle and location
This code indicates the body control module (BCM) has detected an open circuit in the potentiometer feedback circuit of the servo motor that controls the defrost mode door in the HVAC system. The potentiometer provides position feedback to the BCM, and an open circuit means the BCM cannot verify the...
The most common cause of B1269 (Servo Motor Potentiometer Defrost Circuit Open) is: Failed defrost door actuator with internal potentiometer failure or broken wiring harness
Typical repair costs for B1269 range from $150 to $450, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive, but defrost function may not work properly which could impair windshield visibility in cold or humid conditions. Repair should be completed before winter weather or when windshield defogging is needed for safe visibility.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1269 to identify the root cause.
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Quick Info
Category
Body
System
HVAC Climate Control System
Difficulty
Type
Manufacturer
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