Brake Switch Circuit Failure
Your brake switch isn't communicating properly with the vehicle's computer, like a doorbell that won't ring even though you pressed the button. The ECU can't detect when you're pressing the brake pedal, which affects safety systems and transmission logic.
The ECU monitors the brake switch signal voltage, which should toggle between high and low states when the brake pedal is pressed and released. A fault occurs when the switch signal remains stuck in one state, disappears entirely, or shows erratic voltage changes that don't correlate with pedal input.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Brake Switch Signal Voltage | 5V (open) to 0V (closed) with clean transitions | No voltage change, stuck state, or noise/dropout lasting >200ms |
| Signal Consistency | Switch activates within 100ms of pedal press | Delayed, intermittent, or no response to pedal input |
Code C1446 is classified as a serious fault. If your check engine light is flashing — not just steady — pull over safely and do not continue driving. A flashing CEL indicates an active misfire or critical failure that can cause catalytic converter damage within minutes or permanent engine harm within miles. Contact a certified mechanic immediately. Do not attempt roadside repairs on high-severity codes unless you are trained to do so.
Once the fault is repaired, C1446 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.