Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P0106: Manifold Absolute Pressure (MAP) Sensor PerformanceDiagnostic Fault Information
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
|---|---|---|---|---|---|
5-Volt Reference | P0107, P0452, P0532, P0641 | P0106, P0107 | P0107 | P0108, P0533, P0641 | P0106, P0107 |
MAP Sensor Signal | P0107 | P0106, P0107 | P0107 | P0108 | P0106, P0107, P1101 |
Low Reference | -- | P0106, P0108 | P0106, P0108 | -- | P0106, P0108 |
Typical Scan Tool Data
Circuit | Normal Range | Short to Ground | Open | Short to Voltage |
|---|---|---|---|---|
5-Volt Reference | -- | 0 kPa | 0 kPa | 127 kPa |
MAP Sensor Signal | 10-104 kPa | 0 kPa | 0 kPa | 127 kPa |
Low Reference | -- | -- | 80-126 kPa | -- |
Circuit Description
The intake flow rationality diagnostic provides the within-range rationality check for the mass air flow (MAF), manifold absolute pressure (MAP), and the throttle position (TP) sensors. This is an explicit model-based diagnostic containing 4 separate models for the intake system.
| • | The throttle model describes the flow through the throttle body and is used to estimate the MAF through the throttle body as a function of barometric pressure (BARO), TP, intake air temperature (IAT), and estimated MAP. The information from this model is displayed on the scan tool as the MAF Performance Test parameter. |
| • | The first intake manifold model describes the intake manifold and is used to estimate MAP as a function of the MAF into the manifold from the throttle body and the MAF out of the manifold caused by engine pumping. The flow into the manifold from the throttle uses the MAF estimate calculated from the above throttle model. The information from this model is displayed on the scan tool as the MAP Performance Test 1 parameter. |
| • | The second intake manifold model is identical to the first intake manifold model except that the MAF sensor measurement is used instead of the throttle model estimate for the throttle air input. The information from this model is displayed on the scan tool as the MAP Performance Test 2 parameter. |
| • | The fourth model is created from the combination and additional calculations of the throttle model and the first intake manifold model. The information from this model is displayed on the scan tool as the TP Performance Test parameter. |
The estimates of MAF and MAP obtained from this system of models and calculations are then compared to the actual measured values from the MAF, MAP, 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.
MAF Performance Test | MAP Performance Test 1 | MAP Performance Test 2 | TP Performance Test | DTCs Passed | DTCs Failed |
|---|---|---|---|---|---|
-- | -- | OK | OK | P0101, P0106, P0121, P1101 | None |
OK | OK | Fault | OK | P0101, P0106, P0121, P1101 | None |
Fault | OK | Fault | OK | P0106, P0121, P1101 | P0101 |
OK | Fault | Fault | OK | P0101, P0121, P1101 | P0106 |
Fault | Fault | Fault | OK | P0121, P1101 | P0101, P0106 |
-- | -- | OK | Fault | P0101, P0106, P1101 | P0121 |
OK | OK | Fault | Fault | P0101, P0106, P0121, P1101 | None |
Fault | OK | Fault | Fault | P0101, P0106, P0121 | P1101 |
-- | Fault | Fault | Fault | P0101, P0106, P0121 | P1101 |
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 400-8,192 RPM. |
| • | The IAT Sensor parameter is between -7° to +125°C (+19° to +257°F). |
| • | The ECT Sensor parameter is between 70-125°C (158-257°F). |
| • | This DTC runs continuously within the enabling conditions. |
Conditions for Setting the DTC
| • | The engine control module (ECM) detects that the difference between measured MAP and the MAP Performance Test 1 is greater than 20 kPa for greater than 0.5 second. |
| AND |
| • | The ECM detects that the difference between measured MAP and the MAP Performance Test 2 is greater than 20 kPa for greater than 0.5 second. |
| OR |
| • | The ECM detects that the difference between the measured MAF and the MAF Performance Test is greater than 15 g/s for greater than 0.5 second. |
| AND |
| • | The ECM detects that the difference between measured MAP and the MAP Performance Test 1 is greater than 20 kPa for greater than 0.5 second. |
| AND |
| • | The ECM detects that the difference between measured MAP and the MAP Performance Test 2 is greater than 20 kPa for greater than 0.5 second. |
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 wide open throttle (WOT) acceleration from a stop should cause the MAP sensor parameter on the scan tool to increase rapidly to near the BARO Sensor parameter at the time of the 1-2 shift. |
| • | A skewed or stuck engine coolant temperature (ECT) sensor or intake air temperature (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 . |
Reference Information
Schematic Reference
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
Circuit/System Verification
Important: Verify that the engine is in good mechanical condition before continuing with this diagnostic.
| • | Verify the integrity of the entire air induction system by inspecting for the following conditions: |
| - | Any damaged components |
| - | Loose or improper installation |
| - | An air flow restriction |
| - | Any vacuum leak |
| - | Improperly routed vacuum hoses |
| - | In cold climates, inspect for any snow or ice buildup |
| • | Verify that restrictions do not exist in the MAP sensor port or vacuum source. |
| • | Verify that restrictions do not exist in the exhaust system. Refer to Restricted Exhaust . |
| • | The BARO that is used by the ECM to calculate the air flow models is initially based on the MAP sensor at 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. Determine the current vehicle testing altitude. Ignition ON, observe the scan tool BARO Sensor parameter. Compare the parameter to the Altitude vs Barometric Pressure table. Refer to Altitude Versus Barometric Pressure . |
| • | A skewed MAP sensor will also cause the first and second intake manifold models to disagree with the actual MAP sensor measurements. Use the scan tool and compare the MAP Sensor parameter to a known good vehicle, under various operating conditions. |
Circuit/System Testing
- Ignition OFF, disconnect the MAP harness connector at the MAP sensor.
- Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit terminal 2 and ground.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 and ground.
- Verify the scan tool MAP Sensor parameter is less than 1 kPa.
- Install a 3A fused jumper wire between the signal circuit terminal 3 and the 5-volt reference circuit terminal 1. Verify the scan tool MAP Sensor parameter is greater than 125 kPa.
- If all circuits test normal, test or replace the MAP sensor.
Important: All electrical components and accessories must be turned OFF, and allowed to power down.
| ⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. |
| ⇒ | If less than the specified range, test the 5-volt 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-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM. |
| ⇒ | If greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the ECM. |
| ⇒ | If less than the specified range, test the signal circuit terminal 3 for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM. |
Component Testing
- Ignition ON, remove the MAP sensor.
- Install a 3A fused jumper wire between the 5-volt reference circuit terminal 1 and the corresponding terminal of the MAP sensor.
- Install a jumper wire between the low reference circuit terminal 2 of the MAP sensor and ground.
- Install a jumper wire at terminal 3 of the MAP sensor.
- Connect a DMM between the jumper wire from terminal 3 of the MAP sensor and ground.
- Install the J 35555 to the MAP sensor vacuum port. Slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 0-5.2 volts, without any spikes or dropouts.
Important: You must perform the circuit/system testing, in order to verify the integrity of the MAP sensor circuits, before proceeding with the component testing.
| ⇒ | If the voltage is not within the specified range or is erratic, replace the MAP sensor. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for ECM replacement, setup, and programming |
