What Does B1731 Mean?
This diagnostic trouble code indicates that the Body Control Module (BCM) has detected an abnormal voltage condition in the driver's seat rear vertical positioning switch circuit. Specifically, the switch circuit is reading constant battery voltage when it should be at a lower voltage or ground, suggesting a short to power condition. This affects the power seat adjustment system's ability to properly control the rear portion of the seat cushion height.
Common Causes
45%
Damaged or chafed wiring harness causing short to battery voltage in the seat switch circuit, commonly where harness moves with seat adjustment
30%
Faulty seat rear down switch with internal short to power, keeping circuit energized continuously
15%
Corroded or damaged connector terminals at seat switch or seat motor module creating high resistance or short circuit path
10%
Failed seat control module or body control module with internal component failure causing false voltage reading
Diagnostic Steps
1
Step 1: Perform visual inspection of driver's seat wiring harness, especially where it flexes during seat movement, checking for damaged insulation, exposed wires, pinched harness, or signs of chafing against metal seat frame
2
Step 2: Disconnect the seat adjustment switch connector and use a digital multimeter to measure voltage at the rear down switch circuit terminal on the harness side - reading should be 0-1V with ignition on; presence of battery voltage (12V+) confirms short to power in harness
3
Step 3: If battery voltage is present at disconnected harness, isolate fault by disconnecting connectors progressively toward BCM until voltage disappears, identifying the damaged harness section; if no voltage at harness, test switch resistance with multimeter - should read open circuit (infinite ohms) when not pressed
4
Step 4: Repair or replace identified faulty component (harness, switch, or connector), clear codes, cycle seat through full range of motion multiple times, and verify code does not return and proper seat operation is restored
Estimated Repair Cost
$125 - $650
Parts + labor, varies by vehicle and location
This diagnostic trouble code indicates that the Body Control Module (BCM) has detected an abnormal voltage condition in the driver's seat rear vertical positioning switch circuit. Specifically, the switch circuit is reading constant battery voltage when it should be at a lower voltage or ground, sug...
The most common cause of B1731 (Seat Driver Rear Down Switch Circuit Short To Battery) is: Damaged or chafed wiring harness causing short to battery voltage in the seat switch circuit, commonly where harness moves with seat adjustment
Typical repair costs for B1731 range from $125 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 seat adjustment functionality and does not impact vehicle operation or safety systems. Repair at convenience, though continuous electrical short could potentially drain battery if left unaddressed long-term.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1731 to identify the root cause.
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Quick Info
Category
Body
System
Power Seat Adjustment System
Difficulty
Type
Manufacturer
Recommended Tools
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