An Air Brake Pressure Sensor is a key safety and performance component in commercial and heavy-duty vehicles equipped with air brake systems. The sensor continuously monitors air pressure levels within the braking circuit and sends this data to the vehicle’s ECU (Electronic Control Unit) or brake control module.
By ensuring consistent air pressure readings, the system can properly control brake application, optimize braking performance, and detect potential failures such as leaks, pressure drops, or system imbalances — keeping both the driver and vehicle safe on the road.
How It Works:
- Measures real-time air pressure within the braking system.
- Converts mechanical pressure into an electrical signal.
- Sends this signal to the ECU, which monitors brake performance and system integrity.
- Alerts the driver or activates warning lights if abnormal pressure levels are detected.
Product Features & Benefits from Walker Products:
- Exact OE Fit: Direct-fit replacement for fast, accurate installation.
- OE Replacement Quality: Built to meet or exceed OEM specifications.
- Durable Construction: Designed to withstand high vibration, pressure, and moisture exposure.
- Restores Brake Safety: Provides accurate air pressure readings to support safe braking operation.
- Aftermarket Expertise: Backed by over 75 years of experience producing OE replacement sensors.
Symptoms of a Failing Air Brake Pressure Sensor:
- Brake warning light illuminated on the dashboard.
- Inconsistent or unresponsive brake pressure readings.
- Air compressor running excessively or failing to shut off.
- Delayed braking response or uneven brake performance.
- Check Engine Light (CEL) or Brake System Fault indicator active.
Common Check Engine Light (CEL) / OBD-II Codes
To help standardize emissions and system diagnostics, the EPA mandated OBD-II systems for all vehicles from 1996 onward, with advanced diagnostic integration for heavy-duty applications.
The following OBD-II codes are commonly associated with Air Brake Pressure Sensors. These codes are for reference only and should be used as a general guide. Walker Products is not responsible for any use of this information. Always consult a qualified mechanic and follow manufacturer and EPA service procedures when diagnosing, replacing, or resetting components.
- P0579 – Brake Switch “A” Circuit Range/Performance
- P0580 – Brake Switch “A” Circuit High
- P0581 – Brake Switch “A” Circuit Low
- P0578 – Brake Switch “A” Circuit Stuck
- P0571 – Brake Switch “A” Circuit
- P0572 – Brake Switch “A” Circuit Low Input
- P0573 – Brake Switch “A” Circuit High Input
- P2299 – Brake Pedal Position / Accelerator Pedal Position Correlation
- C0045 – Brake Pressure Sensor Circuit
- C0046 – Brake Pressure Sensor Circuit Range/Performance
- C0047 – Brake Pressure Sensor Circuit Low
- C0048 – Brake Pressure Sensor Circuit High
- C0049 – Brake Pressure Sensor Circuit Intermittent