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P006D




DTC P006D

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 provides an overview of each diagnostic category.

DTC Descriptor
DTC P006D
- Supercharger Inlet Pressure (SCIP) - Barometric Pressure (BARO) Correlation

Diagnostic Fault Information










Typical Scan Tool Data










Circuit Description

The barometric pressure (BARO) sensor measures the pressure of the atmosphere. This pressure is affected by altitude and weather conditions. A diaphragm within the BARO sensor is displaced by the pressure changes that occur from varying altitudes and weather conditions. The sensor translates this diaphragm action into the voltage signal input that is used by the engine control module (ECM) for diagnostics and emissions control.

The supercharger inlet absolute pressure sensor measures the absolute pressure of the air just after the throttle body, at the inlet of the supercharger. The plenum volume between the throttle body and the supercharger is where this sensor is located, and for the purpose of this diagnostic, this area is considered to be the intake manifold. The diaphragm within the supercharger inlet absolute pressure sensor functions in the same manner as the BARO sensor. The sensors are not interchangeable.

The purpose of this diagnostic is to analyze the correlation between the BARO sensor and the supercharger inlet absolute pressure sensor. This is accomplished by continually comparing the difference between BARO and supercharger inlet absolute pressure at key ON, engine OFF, at closed throttle idle conditions, and at wide open throttle update events. At key ON, engine OFF the difference between BARO and supercharger inlet absolute pressure is represented on the scan tool by the SC Inlet Pressure parameter as a value that should be very close to zero. A negative SC Inlet Pressure parameter means that the BARO sensor value is less than the supercharger inlet absolute pressure value. A positive SC Inlet Pressure parameter represents a BARO sensor value that is more than the supercharger inlet absolute pressure value.

At idle the SC Inlet Pressure parameter represents the calculated difference between BARO and the reduced pressure that is present in the supercharger intake plenum as a positive value. At wide open throttle the SC Inlet Pressure parameter represents the calculated difference between BARO and the increased pressure that is present in the supercharger intake plenum, and should be very close to zero.

If the ECM detects that the BARO sensor signal and the supercharger inlet absolute pressure sensor signal are not within a calibrated range of each other, DTC P006D sets.

Conditions for Running the DTC

* DTC P0068, P0101, P0102, P0103, P0111, P0112, P0113, P0117, P0118, P0120, P0121, P0122, P0123, P012B, P012C, P012D, P0220, P0222, P0223, P1516, P2101, P2228, or P2229 is not set.
* The engine is running.
* DTC P006D runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects that the difference between actual BARO and calculated BARO is greater than 15 kPa for greater than 5 s.

Action Taken When the DTC Sets

DTC P006D is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P006D is a Type B DTC.

Diagnostic Aids

* Any condition that can cause the BARO or supercharger inlet absolute pressure sensors to be shifted in value may cause this DTC to set.
* A slight to moderate resistance of 20-50 ohm on the 5 V reference terminal 1 or the low reference circuit terminal 2 may cause this DTC to set.
* Inspect the wiring harness of the BARO and supercharger inlet absolute pressure sensors for the improper connections, as this may cause the DTC to set.

Reference Information
Schematic Reference

Engine Controls Schematics [1][2]Electrical Diagrams
Connector End View Reference

Component Connector End Views Connector Views
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
Special Tools

* J23738-A - Mityvac
* J 35555 - Metal Mityvac

Circuit/System Verification

1. Verify that DTC P0106, P0107, P0108, P012B, P012C, P012D, P0641, P0651, P2227, P2228, or P2229 is not set.

• If a of the DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.

2. Ignition ON, engine OFF, observe the SC Inlet Pressure Sensor and BARO Sensor parameters. The readings should be within 5 kPa of each other and the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table for the current testing altitude.
3. Ignition ON, observe the scan tool SC Inlet Pressure Sensor kPa parameter and start the engine. The SC Inlet Pressure Sensor parameter should decrease.
4. 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 Records data.

Circuit/System Testing

1. Verify the integrity of the supercharger inlet absolute pressure and BARO sensors by inspecting for the following conditions:

* Damaged components
* Loose or improper installation
* An air flow restriction
* A cracked or restricted supercharger inlet absolute pressure sensor vacuum hose
* An intake manifold leak

2. Ignition ON, determine which sensor is out of range by comparing SC Inlet Pressure and BARO Sensor kPa parameters with a scan tool. Compare those values to the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table.
3. Ignition OFF, disconnect the harness connector at the appropriate sensor.
4. Ignition OFF and all vehicle systems OFF. It may take up to 2 min for all vehicle systems to power down. Test for less than 5 ohm between the low reference circuit terminal 2 and ground.

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

5. Ignition ON, test for 4.8-5.2 V between the 5 V reference circuit terminal 1 and ground.

• If less than the specified range, test the 5 V reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
• If greater than the specified range, test the 5 V reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.

6. Verify the scan tool sensor parameter is less than 12 kPa.

• If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the ECM.

7. Install a 3 A fused jumper wire between the signal circuit terminal 3 and the 5 V reference circuit terminal 1. Verify the scan tool sensor parameter is greater than 120 kPa.

• If less than the specified range, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

8. If all circuits test normal, test or replace the sensor.

Component Test

Note: You must perform the Circuit/System Testing to verify the integrity of the sensor circuits before proceeding with the Component Testing.

Skewed Signal Test
1. Using the following steps and referencing the table below will determine if the supercharger inlet absolute pressure or BARO sensor is skewed.
2. Ignition ON, engine OFF, observe the appropriate sensor scan tool parameter.
3. Use the observed scan tool sensor pressure parameter that is closest to a value that is indicated in the first column.
THEN
4. Using the J23738-A - Mityvac or the J 35555 - Metal Mityvac, apply 5 in Hg of vacuum to the sensor. The parameter in the first column should decrease by 17 kPa. The acceptable range is indicated in the second column.
5. Using the J23738-A - Mityvac or the J 35555 - Metal Mityvac, apply 10 in Hg of vacuum to the sensor. The parameter in the first column should decrease by 34 kPa. The acceptable range is indicated in the third column.





Erratic Signal Test
1. Ignition OFF, remove the appropriate sensor.
2. Install a 3 A fused jumper between the harness connector 5 V reference circuit terminal 1 and terminal 1 or A of the sensor.
3. Install a jumper wire between the low reference circuit terminal 2 or B of the sensor and ground.
4. Connect a DMM between terminal 3 or C of the sensor and ground.
5. Ignition ON, with the J23738-A - Mityvac or the J 35555 - Metal Mityvac slowly apply vacuum to the sensor while monitoring the voltage on the DMM. The voltage should vary between 0-5.2 V, without any spikes or dropouts.

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

Repair Instructions

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

* Supercharger Air Inlet Pressure Sensor Replacement Supercharger Air Inlet Pressure Sensor Replacement
* Barometric Pressure Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, setup, and programming

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