Brake Pedal Input Open Circuit
The brake pedal sensor has lost electrical connection to the vehicle's computer, like a phone with a broken charging cable. The system can't detect when you're pressing the brake pedal.
The ECU monitors the brake pedal position sensor circuit for proper voltage signals when the brake is pressed and released. It expects a continuous signal within a defined voltage range; an open circuit produces no signal or erratic readings. The ECU sets this code when it detects zero voltage or loss of signal for a calibrated duration.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Brake Pedal Sensor Voltage | 0.5–4.5 V (varies by model) | 0 V or >5 V (open circuit) |
| Signal Continuity | Continuous valid signal | No signal detected >2 seconds |
Code B1484 is a low-severity fault. Your vehicle is generally safe to drive to a workshop for diagnosis. However, do not ignore it indefinitely — low-severity codes often indicate developing problems that become expensive if neglected. Book a diagnostic appointment within 2–4 weeks. If you notice any additional symptoms (rough running, power loss, unusual smells), treat it as higher priority.
Once the fault is repaired, B1484 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.