P16AA

DTC P16AA or P16AB

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provide an overview of each diagnostic category.

DTC Descriptor

DTC P16AA
- Intake Air Heater Temperature Sensor Circuit Low Voltage.

DTC P16AB
- Intake Air Heater Temperature Sensor Circuit High Voltage.

Circuit/System Description

The intake air heater has the ability to perform internal diagnostics for the temperature sensor circuit. The intake air heater monitors the internal temperature sensor voltage and if the voltage falls outside the calibrated threshold, the intake air heater sends a message to the glow plug control module (GPCM) and then the GPCM sends a message to the engine control module (ECM) to set the appropriate DTC.

Conditions for Running the DTC

* Ignition ON.

* The intake air heater battery voltage is greater than 11 V.

* DTC P154D is not set.

* The DTC runs once per trip at ignition key up.

Conditions for Setting the DTC

* A fault is detected when the Intake Air Heater internal temperature voltage falls outside the calibrated threshold for greater than 1.15 S.

Action Taken When the DTC Sets

DTCs P16AA and P16AB are Type B DTCs.

Conditions for Clearing the DTC

DTCs P16AA and P16AB are Type B DTCs.

Reference Information

Schematic Reference

Engine Controls Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views 1-2 Shift Solenoid (SS) Valve (M30)

Description and Operation

Intake Air Heater System Description Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

1. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

• If DTC resets
Refer to Circuit/System Testing.

• If DTC does not reset

2. All OK.

Circuit/System Testing

1. Verify there are no other DTCs present.

• If another DTC is present
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

• If another DTC is not present
Replace the E24 Intake Air Heater.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Intake Air Heater Replacement Service and Repair