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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 Aztek - AWD 🢒 Accessories 🢒 Navigation Systems 🢒 DTC P1106

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 MAP sensor has the following circuits:

    • 5-volt reference circuit
    • Low reference circuit
    • MAP sensor signal circuit

The powertrain control module (PCM) supplies 5 volts to the MAP sensor on the 5-volt reference circuit. The PCM also provides a ground on the low reference circuit. The MAP sensor provides a signal to the PCM on the MAP sensor signal circuit which is relative to the pressure changes in the manifold. The PCM should detect a low signal voltage at a low MAP, such as during an idle or a deceleration. The PCM 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 in order 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 PCM monitors the MAP sensor signal for voltage outside of the normal range.

If the PCM detects a MAP sensor signal voltage that is intermittently high, DTC P1106 sets.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC P1106 Manifold Absolute Pressure (MAP) Sensor Circuit Intermittent High Voltage

Conditions for Running the DTC
    • DTCs P0121, P0122, or P0123 are not set.
    • The engine has been running for a period of time that is determined by the startup coolant temperature. The time ranges from 2 minutes at less than -30°C (-22°F) to 1 second at more than 30°C (86°F).
    • The throttle angle is less than 2 percent when the engine speed is less than 3,000 RPM.
        OR
    • The throttle angle is less than 30 percent when the engine speed is more than 3,000 RPM.

Conditions for Setting the DTC
    • The PCM detects that the MAP sensor voltage is intermittently more than 4.2 volts.
    • DTC P1106 runs continuously when the above condition is met.

Action Taken When the DTC Sets
    • The control module stores the DTC information into memory when the diagnostic runs and fails.
    • The malfunction indicator lamp (MIL) will not illuminate.
    • The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
    • The driver information center, if equipped, may display a message.

Conditions for Clearing the DTC
    • 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 non-emission related diagnostic.
    • Clear the DTC with a scan tool.

Diagnostic Aids

This DTC may set due to poor idle characteristics. A possible cause may be uncontrolled fueling due to an open or high resistance in the HO2S 1 low signal circuit. Before replacing any component, ensure that this condition does not exist.

Test Description

The number below refers to the step number on the diagnostic table.

  1. Many intermittent open or shorted circuits occur with harness/connector movement caused by vibration, by engine torque, and by bumps. This step attempts to recreate this condition.

Step

Action

Yes

No

Schematic Reference: Engine Controls Schematics

Connector End View Reference: Engine Controls Connector End Views or Powertrain Control Module Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2
  1. Start the engine.
  2. Monitor the DTC information with the scan tool.

Does the scan tool display DTC P0641 or P0108 set?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 3

3

  1. Observe the manifold absolute pressure (MAP) sensor parameter with the scan tool.
  2. Attempt to induce the fault that set the DTC by manipulating the following items:
    3. • The MAP sensor wiring harness
    • The MAP sensor connector
    • The powertrain control connector (PCM) connector

Refer to Inducing Intermittent Fault Conditions and Intermittent Conditions .

Is the MAP sensor voltage affected during any part of the test?

Go to Step 4

Go to Step 9

4

Test the low reference circuit between the PCM and the MAP sensor for an intermittent open or a high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Important: Disconnecting the PCM may eliminate the short during the testing.

Test the MAP sensor signal circuit between the PCM and the MAP sensor for an intermittent short to voltage. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Test for an intermittent and for a poor connection at the MAP sensor. Refer to Testing for Continuity and Connector Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 7

7

Test the HO2S 1 low signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 8

8

Test for an intermittent and for a poor connection at the PCM. Refer to Testing for Continuity and Connector Repairs .

Did you find and correct the condition?

Go to Step 9

--

9
  1. Clear the DTCs with a scan tool.
  2. Turn OFF the ignition for 30 seconds.
  3. Start the engine.
  4. 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.

Did the DTC fail this ignition?

Go to Step 2

Go to Step 10

10

Observe the Capture Info with a scan tool.

Are there any DTCs that have not been diagnosed?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

System OK