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DTC P0111-Intake Air Temperature Sensor Rationality: Notes

Fig 1: Intake Air Temperature Sensor Circuit - Circuit Diagram
G04853808Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.

For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article.

Theory of Operation 

Intake Air Temperature Sensor performance looks at the outputs of three temperature sensors and compares them under cold start conditions. Following a start to run delay time, the outputs of the ambient, engine coolant, and intake air temperature sensors will be compared. If the engine coolant and ambient air temperature sensors agree and the intake air temperature does not agree, the intake air temperature sensor is declared as irrational. 

Possible Causes
(K21) IAT SIGNAL CIRCUIT SHORTED TO BATTERY VOLTAGE 
(K21) IAT SIGNAL CIRCUIT OPEN 
(K900) SENSOR GROUND CIRCUIT OPEN 
(K21) IAT SIGNAL CIRCUIT SHORTED TO GROUND 
(K21) IAT SIGNAL CIRCUIT SHORTED TO THE 
(K900) SENSOR GROUND CIRCUIT 
INTAKE AIR TEMPERATURE SENSOR 
PCM 

Always perform the PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before proceeding.