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 Descriptors

DTC P0107: Manifold Absolute Pressure (MAP) Sensor Circuit Low Voltage
DTC P0108: Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance
--- | --- | --- | --- | --- | ---
5-Volt Reference | P0107, P0193, P0236, P0335, P0642 | P0106, P0107 | P0107 | P0193, P0236, P0606, P0643, P0690, P2227 | P0641, P0642, P0643
MAP Sensor Signal | P0107 | P0106, P0107 | P0107 | P0106, P0108 | P0106
Low Reference | -- | P0106 | P0106 | -- | --

### Typical Scan Tool Data

#### MAP Sensor

Circuit | Short to Ground | Open | Short to Voltage
--- | --- | --- | ---
Operating Conditions: Engine running, transmission in Park or Neutral. Parameter Normal Range: 20-48 kPa, varies with altitude.
5-Volt Reference | 0 kPa | 0 kPa | 0-30 kPa
MAP Sensor Signal | 0 kPa | 0 kPa | 255 kPa
Low Reference | -- | 80-250 kPa | --

### Circuit/System Description

The manifold absolute pressure (MAP) sensor has a 5-volt reference circuit, a low reference circuit, and a signal circuit. The engine control module (ECM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit, and provides a ground on the low reference circuit. The MAP sensor provides a voltage signal to the ECM on the signal circuit relative to the intake manifold pressure changes.

The sensor used on this engine is a three atmosphere sensor. Pressure in the intake manifold is affected by engine speed, throttle opening, turbocharger boost pressure, intake air temperature (IAT), and barometric pressure (BARO). Under normal operation the greatest pressure that can exist in the intake manifold at ignition ON, engine OFF is equal to the BARO. When the vehicle is operated at wide-open throttle (WOT), the turbocharger can increase the pressure to near 240 kPa. The least manifold pressure occurs when the vehicle is decelerating and can range from 13-48 kPa.

### Conditions for Running the DTC

• | The ignition is ON, or the engine is running.

• | The DTCs run continuously within the enabling conditions.

### Conditions for Setting the DTC

#### P0107

The ECM detects that the MAP sensor voltage is less than 0.19 volt for more than 4 seconds continuously, or 50 seconds cumulative.

#### P0108

The ECM detects that the MAP sensor voltage is greater than 4.80 volts for more than 4 seconds continuously, or 50 seconds cumulative.

### Action Taken When the DTC Sets

DTCs P0107 and P0108 are Type B DTCs.

### Conditions for Clearing the MIL/DTC

DTCs P0107 and P0108 are Type B DTCs.

### 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 Mityvac

• | J 35555 Metal Mityvac

### Circuit/System Verification

1. Verify that DTCs P0641, P0642, or P0643 are not set.

⇒ | If any of the DTCs are set, refer to DTC P0641-P0643, P0651-P0653, or P0697-P0699.

2. Ignition ON, observe the scan tool MAP sensor parameter. The reading should be between 0.20-4.80 volts.
3. 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. Ignition OFF, disconnect the harness connector at the MAP sensor.
2. Ignition OFF for 90 seconds, test for less than 5 ohms 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.

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

⇒ | 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.

4. Verify the scan tool MAP Sensor parameter is less than 1 kPa.

⇒ | 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.

5. 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 254 kPa.

⇒ | 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.

6. If the circuits test normal, test or replace the MAP sensor.

### Component Testing

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.

#### Erratic Signal Test

1. Ignition OFF, remove the MAP sensor.
2. Install a 3A fused jumper wire between the 5-volt reference circuit terminal 1 and the corresponding terminal of the MAP sensor.
3. Install a jumper wire between the low reference circuit terminal 2 of the MAP sensor and ground.
4. Install a jumper wire at terminal 3 of the MAP sensor.
5. Connect a DMM between the jumper wire from terminal 3 of the MAP sensor and ground.
6. Ignition ON, with the J 23738-A or the J 35555 , 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.

⇒ | 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