🚨 Diagnostic Profile
- Vehicle/Equipment Make: GENERIC
- Technical Description: Brake Booster Pressure Sensor Power Supply Circuit
This code is monitored by the Electronic Brake Control Module (EBCM) and relates to a malfunction in the power supply circuit feeding the brake booster pressure sensor. This sensor is critical for systems utilizing an electro-hydraulic or vacuum-assisted brake booster pump, as it provides real-time pressure data to the EBCM to regulate braking assist. A fault in this circuit—whether due to an open circuit, short to ground, or short to voltage—prevents the module from accurately monitoring booster pressure. This can trigger a reduction in brake assist, illuminate the ABS or Brake warning indicators on the dash, and may disable stability control and traction control functions until the fault is cleared.
🚨 Repair Difficulty Tier
- Difficulty Rating: Intermediate
This repair requires a digital multimeter to test voltage, ground, and resistance values at the sensor connector, as well as a capable scan tool to read live EBCM data and retrieve freeze frame information. While not as complex as internal module replacement, working within the brake system wiring harness requires careful attention to avoid introducing additional electrical faults.
🛠️ Resolution Steps
- Step 1: Preliminary Inspection
Visually inspect the wiring harness and connector leading to the brake booster pressure sensor for signs of chafing, corrosion, melted insulation, or pin damage. Check for loose or corroded connections at the EBCM connector itself, as these are common points of power supply interruption. - Step 2: Diagnostic Verification
Using a digital multimeter, back-probe the sensor connector with the ignition on to verify the reference voltage (typically 5V) is present and stable, and confirm a clean ground signal. Use a scan tool to monitor live brake booster pressure sensor data; an unusually fixed, erratic, or zero-value reading confirms a power supply fault rather than a mechanical booster issue. - Step 3: Resolution & Reset Process
If voltage or ground is missing, repair or replace the damaged wiring segment and connector terminals. If the circuit tests normal but the sensor itself fails calibration checks, replace the pressure sensor assembly. After repairs, clear the stored code using the scan tool and perform a brake system bleed/calibration cycle if required by the vehicle’s service procedure, then conduct a test drive to confirm the code does not return.
📦 Parts, Labor, and Budget Estimates
- Required Components/Software: Brake booster pressure sensor, wiring harness connector/pigtail (if damaged), digital multimeter, bi-directional scan tool with ABS module access
- Average Component Price: $60 – $180 USD
- Estimated Labor Hours: 0.8 – 1.5 hours
- Total Estimated Budget: $140 – $320 USD