Error code

OBD2 P0122

OBD2P0122
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Throttle/Pedal Position Sensor/Switch 'A' Circuit Low.

Severity

moderateCan drive, but performance issues may occur.

Summary

P0122 indicates that the throttle position sensor (TPS) or accelerator pedal position sensor 'A' is providing an abnormally low voltage signal to the engine control module (ECM). This sensor is typically located on the throttle body.

Symptoms

  • Hesitation or stumbling upon acceleration
  • Unstable idle
  • Illuminated check engine light

Common Causes

  • Faulty TPS sensor
  • Open or shorted TPS circuit
  • Corroded electrical connectors
  • Poor battery voltage
  • Contaminant buildup on throttle body

Diagnosis

  1. Visually inspect the sensor and its wiring for corrosion or damage.
  2. Check the throttle body assembly for binding or contamination.
  3. Test the TPS using a multimeter to verify voltage readings at idle and wide open throttle positions.
  4. Inspect the TPS circuit wiring for continuity issues.

Fixes

  • Replace faulty TPS sensor

FAQ

What should I do if my car has P0122?

Start by visually inspecting the throttle position sensor and its wiring. Clean or replace any corroded connectors, and test the TPS with a multimeter to ensure it's functioning correctly.

View source

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.

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