Brake Pedal Position Sensor 1
The brake pedal position sensor 1 is reporting an out-of-range signal.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
Your brake pedal position sensor tells the computer how far you're pressing the brake pedal. If it sends a signal that's too high or too low, the computer thinks something's wrong.
What the computer is actually seeing
The ECU expects the brake pedal position sensor to output a signal voltage typically between 0.5V (pedal released) and 4.5V (pedal fully depressed). If it reads below 0.1V or above 4.9V, it triggers code SPN 2664.
What a healthy reading looks like
The brake pedal position sensor should read between 0.5V and 4.5V in normal operation.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 1Check the wiring and connectors for damage or corrosion before anything else.
- 2Verify that the brake fluid level is adequate; low fluid can affect the sensor.
- 3Using a multimeter, check the signal voltage at the brake pedal position sensor. It should be within 0.5V - 4.5V. If it’s not, proceed to the next step.
- 4Inspect the sensor itself for signs of wear or damage; consider replacing it if it’s faulty based on your voltage readings.
- 5If the sensor checks out, inspect the wiring harness for continuity and opens; repair any issues found.
Common causes
- Faulty brake pedal position sensor
- Damaged wiring or connectors
- Corrosion or debris in the connector
- Brake fluid leakage affecting sensor readings
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
It’s not safe to drive if you notice braking issues. Address this code promptly to ensure braking performance.
Will this code come back after clearing?
If the underlying issue isn't fixed, the code will likely return after clearing once you drive the vehicle.
Why does this code sometimes pair with SPN 2663?
SPN 2663 indicates issues with the brake pedal position sensor 2, suggesting a problem with the braking system as a whole.
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