P1111
IAT Sensor Circuit Intermittent High Voltage
2002-2009 GMC Envoy 4.2L I6
Low SeverityPowertrain
Description
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
- Wiggle test IAT connector while monitoring signal
- Inspect wiring for damage
- Test IAT sensor resistance
- Check connector terminals
Repair Notes
Clean and secure IAT sensor connector. Replace sensor if resistance is out of spec.
Related Codes
P0110Intake Air Temperature (IAT) Sensor 1 CircuitP0111IAT Sensor 1 Circuit Range/PerformanceP0112IAT Sensor 1 Circuit Low InputP0113IAT Sensor 1 Circuit High InputP1112IAT Sensor IntermittentP1112IAT Sensor IntermittentP1112IAT Sensor IntermittentP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112IAT Sensor Circuit Intermittent Low VoltageP1112Intake Air Temperature Sensor Circuit High/IntermittentP1112Intake Air Temperature Sensor Circuit High/IntermittentP1112Intake Air Temperature Sensor Circuit High/Intermittent
Other Powertrain Codes
- P0001Fuel Volume Regulator Control Circuit/Open
- P0001Fuel Volume Regulator Control Circuit/Open
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0002Fuel Volume Regulator Control Circuit Range/Performance
- P0003Fuel Volume Regulator Control Circuit Low
- P0003Fuel Volume Regulator Control Circuit Low
- P0004Fuel Volume Regulator Control Circuit High
- P0004Fuel Volume Regulator Control Circuit High
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
- P0010Intake Camshaft Position Actuator Circuit/Open Bank 1
P1111 on Other Vehicles
Common Questions
What does code P1111 mean on a 2002-2009 GMC Envoy?
P1111 stands for "IAT Sensor Circuit Intermittent High Voltage". The PCM detected intermittent high voltage on the Intake Air Temperature sensor circuit, indicating a sporadic open circuit or connection issue.
What are the symptoms of P1111 on a GMC Envoy?
Common symptoms of P1111 include: Check Engine Light (intermittent), Incorrect fueling in cold weather, Poor fuel economy, Intermittent performance issues.
What causes P1111 on a 2002-2009 GMC Envoy?
Common causes of P1111 include: Loose IAT sensor connector, Intermittent open in wiring, Faulty IAT sensor, Corroded terminals.