P1111low severityPowertrain

IAT Sensor Circuit Intermittent High Voltage

on 2010 GMC Terrain 3.6L V6 · FWD

What this code means

The PCM detected intermittent high voltage on the Intake Air Temperature sensor circuit, indicating a sporadic open circuit or connection issue.

Symptoms

  • Check Engine Light (intermittent)
  • Incorrect fueling in cold weather
  • Poor fuel economy
  • Intermittent performance issues

Common causes

  • Loose IAT sensor connector
  • Intermittent open in wiring
  • Faulty IAT sensor
  • Corroded terminals

Diagnostic steps

  1. Wiggle test IAT connector while monitoring signal
  2. Inspect wiring for damage
  3. Test IAT sensor resistance
  4. Check connector terminals

Repair notes

Clean and secure IAT sensor connector. Replace sensor if resistance is out of spec.

Other Powertrain codes on this vehicle

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