P0106
DTC P0106 (Without Supercharger)
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 P0106
- Manifold Absolute Pressure (MAP) Sensor Performance
Diagnostic Fault Information
Typical Scan Tool Data
Circuit Description
The manifold absolute pressure (MAP) sensor measures the pressure inside the intake manifold. Pressure in the intake manifold is affected by engine speed, throttle opening, air temperature, and barometric pressure (BARO). A diaphragm within the MAP sensor is displaced by the pressure changes that occur from the varying load and operating conditions of the engine. The sensor translates this action into electrical resistance. The MAP sensor wiring includes 3 circuits. The engine control module (ECM) supplies a regulated 5 volts to the sensor on a 5V reference circuit. The ECM supplies a ground on a low reference circuit. The MAP sensor provides a signal voltage to the ECM, relative to the pressure changes, on the MAP sensor signal circuit. The ECM converts the signal voltage input to a pressure value.
Under normal operation the highest pressure that can exist in the intake manifold is equal to BARO. This occurs when the vehicle is operated at wide-open throttle (WOT) or when the ignition is ON while the engine is OFF. Under these conditions, the ECM uses the MAP sensor to determine the current BARO. The lowest manifold pressures occur when the vehicle is idling or decelerating. The ECM monitors the MAP sensor signal for pressure outside of the sensor operating range.
Conditions for Running the DTC
* DTCs P0102, P0103, P0107, P0108, P0112, P0113, P0116, P0117, P0118, P0128, P0335, P0336 are not set.
* The engine speed is between 450-6,700 RPM.
* The IAT Sensor is between -20 and +125°C (-4 and +257°F).
* The ECT Sensor is between -7 and +125°C (+19 and +257°F).
* This DTC runs continuously when the above conditions are met.
Conditions for Setting the DTC
The engine control module (ECM) detects that the MAP sensor pressure is not within range of the calculated pressure that is derived from the system of models for greater than 0.5 S.
Action Taken When the DTC Sets
DTC P0106 is a Type B DTC.
Conditions for Clearing the MIL/DTC
DTC P0106 is a Type B DTC.
Diagnostic Aids
* A skewed or stuck engine coolant temperature (ECT) sensor or IAT sensor will cause the calculated models to be inaccurate and may cause this DTC to run when it should not. Refer to Temperature Versus Resistance Temperature Versus Resistance.
* The barometric pressure (BARO) that is used by the ECM to calculate the air flow models is initially based on the MAP sensor at the ignition ON. When the engine is running, the ECM will continually update the BARO value near WOT using the MAP sensor and a calculation. A skewed MAP sensor will cause the BARO value to be inaccurate.
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
J-23738-A - Vacuum Pump
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
1. If you were sent here from DTC P0068, P0121, P012B, or P1101 refer to Circuit/System Testing - step 1.
2. Ignition ON.
3. Verify the scan tool TB Idle Airflow Compensation parameter is less than 90%.
• 90% or greater
Refer to Throttle Body Cleaning Procedures.
• If less than 90%
4. Verify the scan tool TP Sensors 1 and 2 Agree/Disagree parameter displays Agree while performing the Throttle Sweep Test with a scan tool.
• If Disagree
Refer to DTC P0120-P0123, P0220, P0222, P0223, or P2135 (Without Supercharger) P0120
• If Agree
5. Determine the current vehicle testing altitude.
6. Verify the scan tool MAP Sensor pressure parameter is within the range specified in the Altitude Versus Barometric Pressure Altitude Versus Barometric Pressure table.
• The MAP Sensor pressure is not in range
Refer to Circuit/System Testing - step 1.
• The MAP Sensor pressure is within range
7. Engine idling.
8. Verify the scan tool MAP Sensor pressure parameter is between 26-52 kPa (3.8-7.5 psi) and changes with accelerator pedal input.
• If not between 26-52 kPa (3.8-7.5 psi) or does not change
Refer to Circuit/System Testing - step 1
• If between 26-52 kPa (3.8-7.5 psi) and changes
9. Verify the scan tool MAF Sensor g/s parameter changes smoothly and gradually as the engine speed is increased and decreased while performing the actions listed below.
1. Engine idling
2. Perform the scan tool snapshot function.
3. Increase the engine speed slowly to 3,000 RPM and then back to idle.
4. Exit from the scan tool snapshot and review the data.
5. Observe the MAF Sensor parameter frame by frame with a scan tool.
• The MAF Sensor parameter does not change smoothly and gradually
Refer to DTC P0101 (Without Supercharger) P0101.
• The MAF Sensor parameter changes smoothly and gradually
10. 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.
11. Verify a DTC does not set.
• If the DTC sets
Refer to Circuit/System Testing - step 1.
• If the DTC does not set
12. All OK.
Circuit/System Testing
Note: All electrical components and accessories must be turned OFF and allowed to power down.
1. Verify none of the following conditions exist:
* Loose clamps, cracks, or other damage in the air intake duct system
* Splits, kinks or improper connections at the vacuum hoses
* Vacuum leaks at the intake manifold and throttle body
* A dirty, restricted, or deteriorating air filter element
* A leaking, loose, disconnected, or cracked positive crankcase ventilation (PCV) valve, pipe, or seal
* A collapsed, restricted, or collapsed air intake duct
* A misaligned or damaged air intake duct
* Any objects blocking the air inlet probe of the MAF/IAT sensor
* Any contamination or debris on the sensing elements in the probe of the MAF/IAT sensor
* A cracked or damaged MAF sensor housing
* Any water intrusion in the induction system
* Any snow or ice build-up at the air cleaner, MAF or MAP sensors in cold climates
* Any intake manifold leak
* A MAP sensor seal that is leaking, missing, or damaged
* An Intake Manifold Resonator with a leaking seal, or a cracked or broken housing
* Missing, restricted or leaking exhaust components - Refer to Symptoms - Engine Exhaust Symptoms - Engine Exhaust.
• If a condition exists
Repair or replace component as appropriate.
• If no condition exists
2. Test or replace the B74 manifold absolute pressure sensor.
Component Testing
Note: You must perform the Circuit/System Testing in order to verify the integrity of the MAP sensor circuits before proceeding with the Component Testing.
Skewed Sensor Test
1. Using the following steps and referencing the table below will determine if the B74 manifold absolute pressure sensor is skewed.
2. Ignition ON, engine OFF, observe the MAP Sensor scan tool parameter.
3. Use the observed MAP Sensor Scan Tool parameter that is closest to a value that is indicated in the first column.
THEN
4. Using the J-23738-A - Vacuum Pump to apply 5 in Hg of vacuum to the B74 manifold absolute pressure sensor, the parameter in the first column should decrease by 17 kPa (2.5 psi). The acceptable range is indicated in the second column.
• If not within the acceptable range
Replace the B74 manifold absolute pressure sensor.
• If within the acceptable range
5. Using the J-23738-A - Vacuum Pump to apply 10 in Hg of vacuum to the B74 manifold absolute pressure sensor, the parameter in the first column should decrease by 34 kPa (5.0 psi). The acceptable range is indicated in the third column.
• If not within the acceptable range
Replace the B74 manifold absolute pressure sensor.
• If within the acceptable range
6. All OK.
Erratic Signal Test
1. Ignition OFF, remove the B74 manifold absolute pressure sensor.
2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal C or 1 and the corresponding terminal of the B74 MAP sensor.
3. Install a jumper wire between the low reference terminal A or 2 of the B74 manifold absolute pressure sensor and ground.
4. Install a jumper wire at terminal B or 3 of the B74 manifold absolute pressure sensor.
5. Connect a DMM between the jumper wire from the terminal B or 3 of the B74 manifold absolute pressure sensor and ground.
6. Ignition ON, with the J-23738-A - Vacuum Pump, slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 4.9-0.2 V without any spikes or dropouts.
• If not between 4.9-0.2 V or has spikes or dropouts
Replace the B74 manifold absolute pressure sensor.
• If between 4.9-0.2 V and there are no spikes or dropouts
7. All OK.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* Manifold Absolute Pressure Sensor Replacement (Without LS9) Service and Repair
* Control Module References Control Module References for engine control module replacement, programming, and setup