For 1990-2009 cars

### 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 Performance

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
5-Volt Reference | P0107, P0452, P0651, P2106, P2110 | P0107 | P0108, P0651, P2076 | P0106
MAP Sensor Signal | P0107 | P0107 | P0108 | P0106
Low Reference | -- | P0108, P2106, P2110 | -- | P0106

### Typical Scan Tool Data

#### MAP Sensor

Circuit | Short to Ground | Open | Short to Voltage
--- | --- | --- | ---
Operating Conditions: Engine operating in Closed Loop Parameter Normal Range: 32-48 kPa
5-Volt Reference | 10 kPa | 10 kPa | 50 kPa
MAP Sensor Signal | 10 kPa | 10 kPa | 104 kPa
Low Reference | -- | 98 kPa | 104 kPa*
* Internal ECM or sensor damage may occur if the circuit is shorted to B+.

### Circuit/System Description

The manifold absolute pressure (MAP) sensor responds to pressure changes in the intake manifold. The pressure changes occur based on the engine load. The engine control module (ECM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The ECM provides a ground on the low reference circuit. The MAP sensor provides a signal to the ECM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The ECM detects a low signal voltage at a low MAP, such as during an idle or a deceleration. The ECM detects a high signal voltage at a high MAP, such as the ignition is ON, with the engine OFF, or at a wide open throttle (WOT). The MAP sensor is also used to determine the barometric pressure (BARO). This occurs when the ignition switch is turned ON, with the engine OFF. The BARO reading may also be updated whenever the throttle position (TP) sensor is greater than 28 percent.

### Condition for Running the DTC

• | DTCs P0107, P0108, P0112, P0113, P0117, P0118, P0125, P0261, P0262, P0264, P0265, P0267, P0268, P0270, P0271, P0300, P0301, P0302, P0303, P0304, P0335, P0336, P0351, P0352, P0353, P0354, P0458, P0459, P0502, P0562, P0563, or P2110 are not set.

• | The engine is running.

• | Valid BARO update.

• | The traction control is not active.

• | The torque converter clutch (TCC) is steady (A/T).

• | The A/C compressor clutch is steady.

• | The coolant temperature is greater than -10°C (14°F).

• | The engine speed is between 1,300-4,500 RPM.

• | The change in engine speed is less than 200 RPM.

• | The vehicle speed is greater than 30 Km/h(19 mph).

• | The change in idle air is less than 5 percent.

• | The change in throttle position (TP) is less than 3 percent, or the change in MAP is less than 5 percent.

• | The change in exhaust gas recirculation (EGR) position is less than 6 percent.

• | The above conditions are stabilized for 1.5 seconds.

• | The DTC runs continuously when the above conditions are met.

### Conditions for Setting the DTC

The ECM detects that the actual MAP signal is not within the predicted range for greater than 15 seconds.

### Action Taken When the DTC Sets

DTC P0106 is a Type B DTC.

### Conditions for Clearing the DTC

DTC P0106 is a Type B DTC.

### Diagnostic Aids

• | If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.

• | The scan tool 5 volt reference parameter should display between 4.8-5.2 volts.

### Reference Information

#### Schematic Reference

Engine Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

#### Special Tools

J 23738-A Vacuum Pump

### Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0107, P0108, or P0651 is not set.

⇒ | If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle .

2. Verify none of the following conditions exist:

• | Leaking exhaust gas recirculation (EGR) valve

• | Restricted exhaust--Refer to Restricted Exhaust .

• | Engine mechanical condition--For example, low compression or incorrect timing belt installation. Refer to Symptoms - Engine Mechanical or Timing Belt Inspection .

3. Determine the current vehicle testing altitude. Compare the MAP sensor pressure parameter to the reading in the Altitude Versus Barometric Pressure table . The MAP sensor pressure parameter should be within the specified range indicated in the table.

Important: In extreme cold weather conditions ice may form in the vacuum source to the MAP sensor and may set a DTC. Inspect the MAP sensor and the vacuum source for ice, moisture, or other restrictions.

4. Start the engine and observe the scan tool MAP sensor pressure parameter. The MAP sensor pressure parameter should change while starting the engine.
5. Engine running, observe the scan tool MAP Sensor pressure parameter. The reading should be between 32-48 kPa.
6. Snap the throttle while observing the scan tool MAP sensor pressure parameter. The MAP sensor pressure parameter should change rapidly when the throttle position changes.
7. 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/Failure Records data.

### Circuit/System Testing

1. 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.

2. Ignition OFF, disconnect the vacuum source at the MAP sensor. Connect the J 23738-A to the vacuum hose.
3. Engine running, verify that 15-20 in Hg of vacuum is available to the MAP sensor.

⇒ | If not within the specified range, repair the restriction in the vacuum hose to the MAP sensor.

4. Ignition OFF, connect the vacuum hose to the MAP sensor. Disconnect the harness connector at the MAP sensor.
5. Ignition OFF for 90 seconds, test for less than 5 ohms between the low reference circuit terminal B 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.

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

⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or 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.

7. Verify the scan tool MAP 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.

8. Install a 3A fused jumper wire between the signal circuit terminal C and the 5-volt reference circuit terminal A. Verify the scan tool MAP sensor parameter is greater than 102 kPa.

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

9. If all circuits test normal, test or replace the MAP sensor.

### Component Testing

#### Skewed Signal Test

1. Ignition OFF, remove the vacuum source from the MAP sensor.
2. Ignition ON, observe and record the scan tool MAP sensor pressure data parameter. This is the first MAP sensor reading.
3. With the J 23738-A apply 5 in Hg (17 kPa) of vacuum to the MAP sensor. Observe and record the scan tool MAP sensor pressure data parameter. This is the second MAP sensor reading.
4. Subtract the second MAP sensor reading from the first MAP sensor reading. Verify that the vacuum decrease is within 1 in Hg (4 kPa) of the applied vacuum.

⇒ | If the vacuum decrease is not within the specified range, replace the MAP sensor.

5. With the J 23738-A apply 10 in Hg (34 kPa) of vacuum to the MAP sensor. Observe and record the scan tool MAP sensor pressure data parameter. This is the third MAP sensor reading.
6. Subtract the third MAP sensor reading from the first MAP sensor reading. Verify that the vacuum decrease is within 1 in Hg (4 kPa) of the applied vacuum.

⇒ | If the vacuum is not with in the specified range, replace the MAP sensor.

#### Erratic Signal Test

1. Ignition OFF, remove the vacuum source from the MAP sensor.
2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal A and the corresponding terminal of the MAP sensor.
3. Install a jumper wire between the low reference circuit terminal B of the MAP sensor and ground.
4. Install a jumper wire at terminal B of the MAP sensor.
5. Connect a DMM between the jumper wire from terminal B of the MAP sensor and ground.
6. Ignition ON, install the J 23738-A to the MAP sensor vacuum port. Slowly apply vacuum to the sensor while observing the voltage on the DMM. The voltage should vary between 0.0-5.2 volts, without any spikes or dropouts.

⇒ | If the voltage reading is erratic, replace the MAP sensor.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Manifold Absolute Pressure Sensor Replacement

• | Control Module References for ECM replacement, setup, and programming