Circuit 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 also 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 should detect a low signal voltage at a low MAP, such as during an idle or a deceleration. The ECM should detect 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 engine is operated at WOT. The MAP sensor contains the following circuits:
| • | A 5-volt reference |
| • | A low reference |
| • | A MAP sensor signal |
If the ECM detects the MAP sensor signal is not within the predicted range, this DTC sets.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC P0106 Manifold Absolute Pressure (MAP) Sensor Performance
Condition for Running the DTC
| • | DTC P0101, P0102, P0103, P0122, and P0123 are not set. |
| • | The engine speed is between 1,200-4,000 RPM. |
| • | The mass air flow is between 130-300 mg/stroke. |
| • | The above conditions are met for more than 2 seconds. |
| • | DTC P0106 runs continuously once 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 more than 2 seconds.
Action Taken When the DTC Sets
| • | The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition cycle that the diagnostic runs and fails. |
| • | The control module records the operating conditions at the time the diagnostic fails. The first time the diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic reports a failure on the second consecutive ignition cycle, the control module records the operating conditions at the time of the failure. The control module writes the operating conditions to the Freeze Frame and updates the Failure Records. |
Conditions for Clearing the MIL/DTC
| • | The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail. |
| • | A current DTC, Last Test Failed, clears when the diagnostic runs and passes. |
| • | A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic. |
| • | Clear the MIL and the DTC with a scan tool. |
Diagnostic Aids
The following table illustrates the differences between the engine conditions, the MAP sensor values, and the engine vacuum:
MAP Correlation | |||
|---|---|---|---|
Engine Condition | MAP kPa | MAP Voltage | Engine Vacuum |
Idle | Low | Low | High |
Deceleration | Low | Low | High |
Ignition ON, Engine OFF | High | High | Low |
Wide-Open Throttle | High | High | Low |
For an Intermittent condition, refer to Intermittent Conditions .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step determines if the condition is present.
-
This step tests the MAP sensor's ability to correctly indicate barometric pressure. The value shown for the MAP sensor varies with altitude.
-
This step tests the MAP sensor's ability to respond to an increase in engine vacuum.
-
This step tests the MAP sensor's ability to respond to a sudden decrease in vacuum.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: Engine Controls Schematics Connector End View Reference: Engine Controls Connector End Views or Engine Control Module Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - Engine Controls? | -- | Go to Step 2 | |
2 | Is DTC P0102 also set? | -- | Go to DTC P0102 | Go to Step 3 |
|
Important: If you were sent here from DTC P0101, proceed to step 4.
Does the DTC fail this ignition cycle? | -- | Go to Step 5 | Go to Step 4 | |
4 |
Does the DTC fail this ignition cycle? | -- | Go to Step 5 | Go to Diagnostic Aids |
5 |
Does the TP sensor voltage parameter go from above the specified value to below the specified value? | Above 4.0 V to below 1.0 V | Go to Step 6 | Go to DTC P0121 |
Is the MAP sensor kPa parameter within the specified value of the known good vehicle? | 3 kPa | Go to Step 7 | Go to Step 11 | |
Does the MAP sensor voltage parameter change value after you started the engine? | -- | Go to Step 8 | Go to Step 11 | |
8 |
Does the scan tool indicate that the MAP sensor value changes smoothly through the entire range of the test? | -- | Go to Step 9 | Go to Step 19 |
9 | Observe the MAP sensor kPa display with 20 inches Hg of vacuum applied to the MAP sensor. Does the scan tool indicate that the MAP sensor kPa is less than the specified value? | 34 kPa | Go to Step 10 | Go to Step 11 |
Disconnect the MAP sensor from the hand vacuum pump. The MAP sensor kPa should return to the value observed in step 6. Does the MAP sensor kPa return to the original value that you observed in step 6? | -- | Go to Diagnostic Aids | Go to Step 19 | |
11 |
Does the scan tool indicate that the MAP sensor voltage is more than the specified value? | 0.1 V | Go to Step 17 | Go to Step 12 |
12 |
Is the voltage more than the specified value? | 4.8 V | Go to Step 13 | Go to Step 18 |
13 |
Is the voltage more than the specified value? | 5.5 V | Go to Step 14 | Go to Step 15 |
14 | Test the 5-volt reference circuit of the MAP sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 20 |
15 |
Important: All electrical components and accessories must be turned OFF.
Is the resistance less than the specified value? | 2 ohms | Go to Step 19 | Go to Step 16 |
16 | Test the low reference circuit of the MAP sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 20 |
17 | Test the signal circuit of the MAP sensor for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 20 |
18 | Test the signal circuit and the 5-volt reference circuit of the MAP sensor for high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 20 |
19 | Test for an intermittent and for a poor connection at the MAP sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 21 |
20 | Test for an intermittent and for a poor connection at the ECM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 23 | Go to Step 22 |
21 | Replace the MAP sensor. Refer to Manifold Absolute Pressure Sensor Replacement . Did you complete the replacement? | -- | Go to Step 23 | -- |
22 | Replace the ECM. Refer to Engine Control Module Replacement . Did you complete the replacement? | -- | Go to Step 23 | -- |
23 |
Did the DTC fail this ignition? | -- | Go to Step 2 | Go to Step 24 |
24 | Observe the Capture Info with a scan tool. Are there any DTCs that have not been diagnosed? | -- | System OK | |
