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
- Barometric Pressure (BARO) - Supercharger Inlet Pressure Correlation
Circuit/System 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 displacement into the voltage signal input that is used by the engine control module (ECM) for diagnostics and emissions control.
The supercharger inlet 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 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 pressure sensor. This is accomplished by continually comparing the difference between BARO and supercharger inlet pressure at key ON, engine OFF, closed throttle idle conditions and at wide open throttle update events. At key ON, engine OFF, the difference between BARO and the supercharger inlet pressure should be very close to zero, and is represented on the scan tool by the SC Inlet Pressure parameter. A negative SC Inlet Pressure parameter means that the BARO sensor value is less than the supercharger inlet pressure value. A positive SC Inlet Pressure parameter represents a BARO sensor value that is greater than the supercharger inlet pressure value.
At idle the SC Inlet Pressure parameter should be a positive value and represents the calculated difference between BARO and the reduced pressure that is present in the supercharger intake plenum. At wide open throttle the SC Inlet Pressure parameter should be very close to zero and represents the calculated difference between BARO and the increased pressure that is present in the supercharger intake plenum.
If the ECM detects that the BARO sensor signal and the supercharger inlet pressure sensor signal are not within a calibrated range, 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 BARO and SC Inlet Pressure is greater than 15 kPa (2.2 psi) for greater than 5 s.
Action Taken When the DTC Sets
DTC P006D is a Type B DTC.
Conditions for Clearing the DTC
DTC P006D is a Type B DTC.
Diagnostic Aids
* Any condition that can cause the BARO or supercharger inlet pressure sensors to be shifted in value may cause this DTC to set.
* A resistance of 20-50 ohms on the 5 V reference terminal 1 or the low reference circuit terminal 2 may cause this DTC to set.
* The harness connectors for the BARO sensor and the supercharger inlet pressure sensor are of the same configuration but are not interchangeable. Review the engine controls schematics for the BARO sensor and the supercharger inlet pressure sensor and note the circuit colors. Inspect the wiring harnesses of both sensors for the proper connections.
Reference Information
Schematic Reference
Engine Controls Schematics (LS3) [1][2]Electrical DiagramsEngine Controls Schematics (LS7) [1][2]Electrical DiagramsEngine Controls Schematics (LS9) [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views 5 Bow Lowered Switch (CM7)
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
Circuit/System Verification
1. Verify that DTC P0106, P0107, P0108, P012B, P012C, P012D, P0641, P0651, P2227, P2228, or P2229 is not set.
• If a DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.
2. Determine the current vehicle testing altitude.
3. Ignition ON. Verify the scan tool BARO parameter is within the range specified in the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table.
• The BARO parameter is not in range
Refer to DTC P2227 P2227 for further diagnosis.
• The BARO parameter is within range
4. Verify the scan tool SC Inlet Pressure Sensor pressure parameter is within range specified in the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table.
• The SC Inlet Pressure Sensor pressure is not in range
Refer to DTC P012B P012B for further diagnosis.
• The SC Inlet Pressure Sensor pressure is within range
5. Verify the SC Inlet Pressure Sensor pressure parameter decreases after starting the engine.
• The SC Inlet Pressure Sensor pressure does not decrease
Refer to Circuit/System Testing.
• The SC Inlet Pressure Sensor pressure decreases
6. Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
7. Verify a DTC does not set.
• If any DTC sets
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle for further diagnosis.
• If no DTCs set
8. All OK
Circuit/System Testing
Note: You must perform Circuit/System Verification before proceeding with the Circuit/System Testing.
1. Verify none of the following conditions exist:
* Loose clamps, cracks, or other damage in the air intake duct system
* Collapsed or restricted air intake duct system
* Restricted air filter
* Splits, kinks or improper connections at the vacuum hoses
* Missing, restricted or leaking exhaust components-Refer to Symptoms - Engine Mechanical Symptoms - Engine Mechanical.
* Vacuum leaks at the intake manifold and throttle body
• If a condition exists, repair as necessary.
• If no condition exists.
2. Verify the integrity of the supercharger system by inspecting for the following conditions:
* A binding or restricted supercharger bypass valve, linkage or actuator. Refer to Supercharger Cleaning and Inspection
* Any damaged components
* Loose or improper installation of any components
* An air flow restriction
* Any vacuum leaks
* Water intrusion
* Snow or ice buildup, if applicable
* Missing or leaking seal on the B105 supercharger inlet pressure sensor or B17 barometric pressure sensor
* Contamination or debris blocking or restricting the B105 supercharger inlet pressure sensor or B17 barometric pressure sensor port
• If a condition exists, repair as necessary.
• If no condition exists.
3. Test the B105 supercharger inlet pressure sensor and the B17 barometric pressure sensor.
Component Test
Note: You must perform the Circuit/System Testing before proceeding with the Component Testing.
Skewed Signal Test
1. Ignition OFF, remove the appropriate sensor.
2. Ignition ON, apply 5 in Hg of vacuum to the sensor, with the J23738-A. Verify the corresponding scan tool pressure parameter decreases between 13-21 kPa (1.8-3.0 psi).
• If the pressure does not decrease between 13-21 kPa (1.8-3.0 psi)
Replace the sensor.
• If the pressure decreases between 13-21 kPa (1.8-3.0 psi)
3. Apply 10 in Hg of vacuum to the sensor with the J23738-A. Verify the corresponding scan tool pressure parameter decreases between 30-38 kPa (4.4-5.5 psi).
• If the pressure does not decrease between 30-38 kPa (4.4-5.5 psi)
Replace the sensor.
• If the pressure decreases between 30-38 kPa (4.4-5.5 psi)
Erratic Signal Test
1. Ignition OFF, install a 3 A fused jumper between the harness connector 5 V reference circuit terminal 1 and terminal 1 or A of the sensor.
2. Install a jumper wire between the low reference circuit terminal 2 or B of the sensor and ground.
3. Ignition ON, Test for 5.2-0 V between the signal terminal 3 and the low reference terminal 2, and verify there are NO spikes or dropouts in the voltage signal while slowly applying vacuum to the sensor with the J 23738-A.
• If not between 5.2-0 V or has spikes or dropouts
Replace the sensor.
• If between 5.2-0 V and there are no spikes or dropouts
4. All OK
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the repair.
* Supercharger Air Inlet Pressure Sensor Replacement (LS9)
* Barometric Pressure Sensor Replacement Service and Repair
* Control Module References Control Module References for ECM replacement, programming, and setup