What Does B1237 Mean?
This code indicates the Body Control Module (BCM) has detected an abnormal feedback signal from a power window position sensor or motor assembly. The feedback signal is outside the expected voltage or resistance range, preventing the module from accurately determining window position. This typically occurs during window operation when the BCM cannot verify proper motor response or glass travel.
Common Causes
40%
Faulty window motor or internal position sensor/feedback circuit within the motor assembly
30%
Damaged, corroded, or loose wiring/connectors between BCM and window motor
20%
Failed window regulator causing binding or mechanical resistance affecting feedback
10%
Body Control Module internal circuit failure or software corruption
Diagnostic Steps
1
Step 1: Perform visual inspection of the affected window motor connector and wiring harness for corrosion, damaged pins, water intrusion, or loose connections. Check for proper seating of connector and inspect door jamb area for pinched or damaged wires.
2
Step 2: Using a digital multimeter, backprobe the window motor connector while operating the window switch. Verify voltage supply (typically 12V during operation) and check feedback signal wire for proper voltage range (typically 0.5-4.5V varying with position). Compare readings to manufacturer specifications.
3
Step 3: Remove door panel and manually test window regulator for smooth operation, binding, or excessive resistance. Check for broken regulator cables, damaged tracks, or obstructions preventing normal glass movement.
4
Step 4: With door panel removed and motor connector accessible, swap the suspect motor with a known-good motor or test motor independently using a bench power supply while monitoring feedback signal output with multimeter to isolate motor failure.
5
Step 5: Clear the code and perform window calibration/initialization procedure if available in scan tool functions. Cycle window through full up/down range multiple times and monitor live data for feedback voltage consistency.
6
Step 6: If all components test normal, inspect BCM connectors for corrosion and perform BCM power/ground tests. Consider BCM replacement or reprogramming only after confirming all other components and wiring are verified functional.
Estimated Repair Cost
$150 - $650
Parts + labor, varies by vehicle and location
This code indicates the Body Control Module (BCM) has detected an abnormal feedback signal from a power window position sensor or motor assembly. The feedback signal is outside the expected voltage or resistance range, preventing the module from accurately determining window position. This typically...
The most common cause of B1237 (Window Feedback Out of Range) is: Faulty window motor or internal position sensor/feedback circuit within the motor assembly
Typical repair costs for B1237 range from $150 to $650, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Safe to continue driving as this only affects power window operation convenience. However, a non-functioning window may pose security concerns and inability to adjust ventilation. Address within a reasonable timeframe but not an emergency repair.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1237 to identify the root cause.
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Quick Info
Category
Body
System
Power Window System
Difficulty
Type
Manufacturer
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