What Does P1051 Mean?
The powertrain control module is not receiving a proper signal from the brake pedal position switch. This switch tells the ECM when the brake pedal is pressed, which is critical for fuel cutoff, cruise control, and transmission shift logic.
Common Causes
45%
Faulty brake pedal position switch or brake light switch
30%
Damaged or corroded wiring/connector between brake switch and ECM
15%
Misadjusted brake switch position or mounting bracket
10%
Blown fuse or poor ground connection in brake switch circuit
Diagnostic Steps
1
Step 1: Verify brake lights operate correctly and check for blown fuses
2
Step 2: Test brake switch operation with multimeter while pressing/releasing pedal
3
Step 3: Inspect wiring harness and connectors for damage, corrosion, or loose connections
4
Step 4: Check switch adjustment and mounting position per manufacturer specifications
5
Step 5: Monitor live data for brake switch signal voltage while operating pedal
Estimated Repair Cost
$75 - $250
Parts + labor, varies by vehicle and location
The powertrain control module is not receiving a proper signal from the brake pedal position switch. This switch tells the ECM when the brake pedal is pressed, which is critical for fuel cutoff, cruise control, and transmission shift logic.
The most common cause of P1051 (Brake Switch Signal Missing or Improper) is: Faulty brake pedal position switch or brake light switch
Typical repair costs for P1051 range from $75 to $250, depending on the vehicle, location, and whether you do it yourself or go to a shop.
May affect cruise control deactivation, transmission shift points, and fuel cutoff during braking. Vehicle remains drivable but monitor for unexpected behavior during braking events.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P1051 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Powertrain Control and Brake System Interface
Difficulty
Type
Manufacturer
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
