TorqueMech OBD Code Guide
P0120 - Throttle/Pedal Position Sensor/Switch A Circuit Malfunction
Problem detected in TPS/APP circuit A.
Code first. Confirm symptoms and checks before pricing parts.
Read code pattern
Check likely system
Estimate after confirmation
Code Overview
Problem detected in TPS/APP circuit A.
Common Causes
- TPS/APP sensor failed
- Wiring/connectors issue
- Throttle body contamination (some systems)
Diagnostic Steps
- Check TPS/APP readings sweep smoothly
- Inspect harness near throttle body
- Check for 5V reference/ground
- Perform throttle relearn if applicable
Related OBD Codes
Browse nearby codes when systems overlap.
Next Steps
Move from code to checks, then estimate.