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

Important: The following applies to the intake airflow system performance diagnostic that is used in this supercharged engine:

The intake airflow system performance diagnostic provides the within-range rationality check for the mass air flow (MAF), supercharger inlet absolute pressure (SCIP), MAP, by-pass valve stuck, and the throttle position (TP) sensors. This is an explicit model-based diagnostic containing 4 separate models for the intake system.

The estimates of MAF, SCIP, and TP that are obtained from this system of models and calculations are then compared to the actual measured values from the MAF, SCIP, and the TP sensors and to each other to determine the appropriate DTC to fail. The following table illustrates the possible failure combinations and the resulting DTC or DTCs.

DTC P0106 is a Type A DTC.

DTC P0106 is a Type A DTC.

Caution: Refer to Road Test Caution in the Preface section.

Schematic Reference

Engine Controls Schematics

Connector End View Reference

Electrical Information Reference

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Special Tools Required

J 35555 Metal Mityvac

Important: Verify that the engine is in good mechanical condition before continuing with this diagnostic.

1. If DTCs P0069, P0107, P0108 are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for further information.

Important: The Altitude vs. Barometric Pressure table indicates a pressure range for a given altitude under normal weather conditions. Weather conditions consisting of very low or very high pressure and/or very low or very high temperature may cause a reading to be slightly out of range.

2. Ignition ON, observe the scan tool MAP, SC Inlet Pressure, and BARO parameters. Verify the MAP, SC Inlet Pressure, and BARO sensor parameters are within 5 kPa of each other.
3. Ignition ON, observe the MAP Sensor kPa parameter with a scan tool. Start the engine. The MAP Sensor kPa parameter should decrease.
4. Engine running at idle, observe and record the MAP Sensor parameter kPa value with a scan tool. Slowly increase the engine speed from idle to 2,000 RPM, then allow the engine speed to return idle. The MAP sensor parameter should increment to a higher value at 2,000 RPM and return to the recorded idle value.
5. Verify the integrity of the air induction system by inspecting for the following conditions:

•	Damaged components

•	Loose or improper installation

•	An air flow restriction

•	A cracked or restricted MAP sensor vacuum hose

•	An intake manifold leak

6. Ignition ON, compare APP sensors 1 and 2 percentages with a scan tool. Verify that they do not differ more than 5 percent when a slow pedal sweep is performed.

Important: You must perform the circuit/system verification before proceeding with the circuit/system testing.

1. Ignition OFF, disconnect the harness connector at the MAP sensor.
2. Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit terminal and ground.

⇒	If greater than the specified range, test the low reference circuit for an open or high resistance. If the circuit tests normal, replace the control module.

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal and ground.

⇒	If less than the specified range, test the 5-volt reference circuit for a short to ground, open, or high resistance. If the circuit tests normal, replace the control module.

⇒	If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the control module.

4. Verify the scan tool MAP Sensor parameter is less than 0.2 volt.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the control module.

5. Install a 3A fused jumper wire between the signal circuit terminal and the 5-volt reference terminal. Verify the scan tool MAP Sensor parameter is greater than 200 kPa.

⇒	If less than the specified range, test the signal circuit for a short to ground, open, or high resistance. If the circuit tests normal, replace the control module.

6. If all circuits test normal, test the MAP sensor. Refer to Component Testing

Important: You must perform the circuit/system verification before proceeding with the circuit/system testing.

1. Ignition OFF, remove the MAP sensor.
2. Install a 3A fused jumper wire between the 5-volt reference terminal of the sensor and 5 volts.
3. Install a jumper wire between the low reference terminal of the sensor and ground.
4. Ignition ON, install the J 35555 to the MAP sensor vacuum fitting. Slowly apply vacuum to the sensor while monitoring the voltage between the signal terminal and the low reference terminal. the voltage should vary between 5-0 volts, without any spikes or dropouts.

⇒	If the voltage is not within the specified range or is erratic, replace the MAP sensor.

1. Ignition ON, observe the MAP, SC Inlet Pressure, and BARO parameters with a scan tool. The MAP, SC Inlet Pressure, and BARO sensor parameters should be within 5 kPa of each other.
2. With a scan tool, command the supercharger bypass control valve ON. Slowly increase the engine speed from idle to 2,000 RPM and return the engine to idle speed.

⇒	The MAP sensor parameter should increment to a higher value and return to the normal idle value.