Circuit DescriptionThe turbocharger compressor intake temperature sensor is a variable resistor sensor and is used to measure the temperature of the air entering the compressor intake of the turbocharger. The engine control module (ECM) supplies 5-VDC to the compressor intake temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the air temperature.

Component LocationThe turbocharger compressor intake temperature sensor is located in the compressor inlet of the turbocharger.

Conditions for Running the DiagnosticsThis diagnostic consists of two parts:

The first part runs when the keyswitch is turned to the ON position after a 8 hour cold soak, during which the keyswitch has been turned OFF.The second part runs continuously while the engine is running.Conditions for Setting the Fault CodesThe Engine Control Module (ECM) detected the compressor intake temperature reading was too high or too low for the engine operating conditions.

Action Taken When the Fault Code is ActiveThe ECM illuminates the amber CHECK ENGINE lamp and/or the Malfunction Indicator Lamp (MIL) immediately when the diagnostic runs and fails.A default value for the compressor intake temperature reading is used.Diesel exhaust fluid injection into the aftertreatment system is disabled.Active and stationary regeneration of the diesel particulate filter will be disabled.Exhaust Gas Recirculation (EGR) valve operation will be disabled.Engine torque will be reduced if the engine is operated for an extended period of time with this fault active.Conditions for Clearing the Fault CodeTo validate the repair, perform a key cycle, start the engine and let it idle for 1 minute.If the fault code does not go inactive, it may be necessary to perform a 8 hour cold soak with the key OFF, then turn the keyswitch to the ON position so that the key ON portion of the diagnostic will run.The fault code status displayed by INSITE™ electronic service tool will change to INACTIVE immediately after the diagnostic runs and passes.The ECM will turn off the amber CHECK ENGINE lamp immediately after the diagnostic runs and passes.For On-Board Diagnostics (OBD) engines, the ECM will extinguish the Malfunction Indicator Lamp (MIL) after three consecutive trips where the diagnostic runs and passes.The Reset All Faults command in INSITE™ electronic service tool can be used to clear active and inactive faults, as well as extinguish the MIL for OBD applications.

Shop TalkPossible causes of this fault code include:

Stuck in-range compressor intake temperature sensorHigh resistance in the compressor intake temperature sensor signal or return linesECM malfunction.

Possible Cause:1) ECM failure