OBD Guide

P1123

Throttle Position Sensor Circuit Intermittent High Voltage

Severity
⚠️ Medium
Can you drive?
Limited driving only, diagnose soon
Approx. repair cost
$17–56 (est.)

Symptoms

  • Unstable engine idling
  • Dips during acceleration
  • Increased fuel consumption
  • Check Engine Light Is On
  • Reduced engine power

Causes

  • Throttle Position Sensor Malfunction
  • Open or short circuit in the sensor circuit
  • Oxidation of contacts in connectors
  • Circuit Grounding Problems
  • Malfunction of the engine control unit (rare)

How to Fix

  1. Check the condition of the sensor connectors and wiring
  2. Clean contacts from oxides
  3. Check the sensor resistance (compare with standards)
  4. Replace the throttle position sensor if necessary
  5. Check and restore the integrity of the power circuit and signal wire

Related codes

Error P1123 by Vehicle Brand