GM Service Manual Online
For 1990-2009 cars only

Object Number: 404075  Size: SF
Engine Controls Components
OBD II Symbol Description Notice
A/C Refrigerant Pressure Sensor, TP, MAP, ECT and IAT Sensor
Handling ESD Sensitive Parts Notice
Handling ESD Sensitive Parts Notice

Circuit Description

VIN K

The manifold absolute pressure (MAP) sensor responds to changes in the intake manifold pressure or vacuum. The PCM supplies a 5-volt reference and ground for the MAP sensor. The MAP sensor provides a signal to the PCM that is relative to the pressure changes in the manifold. The MAP sensor signal voltage to the PCM varies from less than 2 volts at idle, where a low manifold absolute pressure indicates a high vacuum, to more than 4 volts with the key ON, and the engine not running or at wide-open throttle, where a high manifold absolute pressure indicates a low vacuum. The PCM monitors the MAP signal for voltages outside the normal range of the MAP sensor. If the PCM detects a MAP signal voltage that is intermittently high, DTC P1106 will set.

VIN 1

The MAP sensor responds to changes in the intake manifold pressure. The PCM supplies a 5-volt reference and a ground for the MAP sensor. The MAP sensor provides a signal to the PCM that is relative to the pressure changes in the manifold. With the key ON, and the engine not running, the MAP sensor signal voltage to the PCM varies from 1.5 volts to 2.5 volts. With the engine running, the MAP sensor voltage to the PCM varies from less than 2 volts at idle, indicating a low manifold absolute pressure and a high vacuum, to more than 4 volts at wide-open throttle, indicating a high manifold absolute pressure and a low vacuum. The PCM monitors the MAP signals for voltage that is outside the normal range of the MAP sensor. If the PCM detects a MAP signal voltage that is intermittently high, DTC P1106 will set.

Conditions for Running the DTC

    • No TP sensor DTCs are present.
    • The ignition is ON.
    • The throttle angle is steady below 2 percent if the engine speed is less than 900 RPM.

Conditions for Setting the DTC

The MAP sensor intermittently indicates a voltage that is more than 4.2 volts.

Action Taken When the DTC Sets

The PCM stores conditions which were present when the DTC set as Failure Records only. This information will not be stored as Freeze Frame Records.

Conditions for Clearing the MIL/DTC

    • The DTC becomes history when the conditions for setting the DTC are no longer present.
    • The history DTC clears after 40 malfunction free warm-up cycles.
    • The PCM receives a clear code command from the scan tool.

Diagnostic Aids

Inspect for the following conditions:

Many situations may lead to an intermittent condition. Perform each inspection or test as directed.

Important: :  Remove any debris from the connector surfaces before servicing a component. Inspect the connector gaskets when diagnosing or replacing a component. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion.

    • Loose terminal connection
       -  Use a corresponding mating terminal to test for proper tension. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair.
       -  Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connection. Refer to Testing for Intermittent Conditions and Poor Connections , and to Connector Repairs in Wiring Systems for diagnosis and repair.
    • Damaged harness--Inspect the wiring harness for damage. If the harness inspection does not reveal a problem, observe the display on the scan tool while moving connectors and wiring harnesses related to the sensor. A change in the scan tool display may indicate the location of the fault. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair.
    •  Inspect the powertrain control module (PCM) and the engine grounds for clean and secure connections. Refer to Wiring Repairs in Wiring Systems for diagnosis and repair.

If the condition is determined to be intermittent, reviewing the Snapshot or Freeze Frame/Failure Records may be useful in determining when the DTC or condition was identified.

DTC P1106 - MAP Sensor Circuit Intermittent High Voltage

Step

Action

Value(s)

Yes

No

1

Did you perform the Powertrain On Board Diagnostic (OBD) System Check?

--

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

2

Important:  If DTC P1635 5 Volt Reference Circuit is set, perform that diagnostic first.

Is DTC P0108 also set?

--

Go to DTC P0108 Manifold Absolute Pressure (MAP) Sensor Circuit High Voltage

Go to Step 3

3

Is DTC P1111, P1115, and/or P1121 also set?

--

Go to Step 6

Go to Step 4

4

  1. Inspect the ground circuit of the MAP sensor for a poor connection at the harness connector. Refer to Testing for Intermittent Conditions and Poor Connections .
  2. If you find a problem, repair the condition as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 5

5

  1. Inspect the ground circuit of the PCM for a poor connection at the harness connector. Refer to Testing for Intermittent Conditions and Poor Connections .
  2. If you find a problem, repair the condition as necessary. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 6

6

Test the signal circuit of the MAP sensor for an intermittent short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

7

Test the 5-volt reference A circuit of the MAP for an intermittent short to voltage. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

8

Test the ground circuit for an intermittent open.

Did you find and correct the condition?

--

Go to Step 9

Go to Diagnostic Aids

9

  1. Use a scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC, as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK