What Does B1726 Mean?
This diagnostic trouble code indicates that the Body Control Module (BCM) has detected an open circuit in the driver's seat rear vertical adjustment switch circuit. The BCM monitors the electrical continuity of the seat adjustment switch inputs and has identified that no signal is being received from the rear up switch position, suggesting a break in the wiring, a faulty switch, or a poor connection. This affects the power seat adjustment system's ability to raise the rear portion of the driver's seat.
Common Causes
45%
Faulty driver seat rear vertical adjustment switch assembly with internal open circuit or worn contacts
30%
Broken or damaged wiring between the seat switch and BCM, often due to seat movement or wire chafing
15%
Corroded or loose electrical connector at the seat switch or BCM connection point
10%
Failed body control module with damaged input circuit for seat control
Diagnostic Steps
1
Step 1: Perform a visual inspection of the driver seat adjustment switch assembly for physical damage, wear, or loose mounting. Check all visible wiring near the seat track for fraying, pinching, or damage from seat movement.
2
Step 2: Disconnect the seat adjustment switch connector and inspect pins for corrosion, bent terminals, or moisture intrusion. Clean connector terminals with electrical contact cleaner if corrosion is present.
3
Step 3: Using a digital multimeter, test continuity across the rear up switch terminals while manually activating the switch. Expected reading should be near 0 ohms when pressed and infinite ohms when released. If no continuity is present when pressed, the switch is faulty.
4
Step 4: If switch tests good, check continuity of the wiring harness between the switch connector and BCM connector using a wiring diagram. Look for open circuits indicating broken wires, particularly in flex points under the seat.
5
Step 5: Test voltage supply to the switch assembly from the BCM (typically 5V or 12V reference depending on manufacturer). Lack of supply voltage indicates a BCM or power distribution issue.
6
Step 6: After repairs, clear the code and cycle the seat rear up function multiple times to verify proper operation and confirm the code does not return.
Estimated Repair Cost
$150 - $650
Parts + labor, varies by vehicle and location
This diagnostic trouble code indicates that the Body Control Module (BCM) has detected an open circuit in the driver's seat rear vertical adjustment switch circuit. The BCM monitors the electrical continuity of the seat adjustment switch inputs and has identified that no signal is being received fro...
The most common cause of B1726 (Seat Driver Rear Up Switch Circuit Open) is: Faulty driver seat rear vertical adjustment switch assembly with internal open circuit or worn contacts
Typical repair costs for B1726 range from $150 to $650, depending on the vehicle, location, and whether you do it yourself or go to a shop.
This code does not present a safety risk and the vehicle is safe to drive. The only impact is loss of rear vertical adjustment function for the driver's seat, which affects comfort but not vehicle operation or safety systems.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to B1726 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Body
System
Body Control System - Power Seat Adjustment
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
