B1483
Brake Pedal Input Circuit Failure
Body Chassis/Safety Brake System Input 🟢 Low — Fix at next service
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What This Actually Means
In plain language — no jargon

The brake pedal switch isn't communicating properly with the vehicle's computer, like a light switch that won't send a signal when flipped. This prevents the ECU from knowing when you're pressing the brake pedal.

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Symptoms You May Notice
3 known symptoms for this code
Brake lights not illuminating when pedal is pressed
Cruise control inoperative or won't engage
ABS or traction control warning lights activated
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Embedded Systems Insight
What the ECU/ECM is actually computing

The ECU monitors the brake pedal position switch voltage signal to detect brake application. It expects a clean digital transition from high to low voltage when the pedal is depressed. A missing, intermittent, or out-of-range signal triggers this fault.

Voltage & Parameter Thresholds

Parameter Normal Range Fault Condition
Brake Switch Voltage 5V when released, 0V when pressed No signal change or stuck at one level
Signal Response Time < 100ms transition No transition detected or > 500ms delay
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Diagnostic & DIY Fix Guide
Check these in order — from cheapest to most complex
1
Brake pedal switch connector
Disconnect and reconnect the brake switch harness to reseat any corroded contacts.
2
Brake pedal switch assembly
Replace the switch located under the dashboard above the brake pedal if it's stuck or damaged.
3
Wiring harness and connectors
Inspect the entire brake switch circuit for broken wires, corrosion, or loose connections between switch and ECU.