GM Service Manual Online
For 1990-2009 cars only

Object Number: 154580  Size: MF
Engine Controls Components
Engine Data Sensors
OBD II Symbol Description Notice

Circuit Description

The manifold absolute pressure (MAP) sensor responds to changes in the intake manifold pressure. The powertrain control module (PCM) supplies a 5 volt reference and a ground for the MAP sensor. The MAP sensor provides a signal to the PCM relative to the pressure changes in the manifold. The MAP sensor signal voltage to the PCM varies from below 2 volts at idle to above 4 volts with the key on and the engine not running or at wide-open throttle. The PCM monitors the MAP signals for voltage outside the normal range of the MAP sensor. If the PCM detects a MAP signal voltage that is intermittently high, DTC P1106 is set.

Conditions for Running the DTC

  1. No throttle position (TP) sensor DTCs are present.
  2. The ignition is on.
  3. The throttle angle is steady below 2% if the engine speed is less than 900 RPM.

Conditions for Setting the DTC

The MAP sensor intermittently indicates a voltage greater than 4.2 volts.

Action Taken When the DTC Sets

The PCM stores the conditions which were present when the DTC set as Fail Records data only.

Conditions for Clearing the MIL/DTC

    • A history DTC clears after 40 consecutive warm-up cycles have occurred without a malfunction.
    • DTC may be cleared by using the scan tool Clear Info function or by disconnecting the PCM battery feed.

Diagnostic Aids

Inspect for the following conditions:

  1. A faulty connection at the PCM or the MAP sensor. Inspect the harness connectors for backed out terminals, improper mating, broken locks, improperly formed or damaged terminals, and faulty terminal to wire connections.
  2. Inspect the wiring harness for damage. If the harness appears to be OK, observe the MAP display on a scan tool while moving the connectors and wiring harnesses related to the sensor. A change in the display indicates the location of the malfunction.

Reviewing the Fail Records vehicle mileage since the diagnostic test last failed may help determine how often the condition that caused the DTC to be set occurs. This may assist in diagnosing the condition.

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

Use a scan tool in order to select DTC Info, Last Tst Fail, and note any other DTCs set.

Is DTC P0108 also set?

--

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

Go to Step 3

3

Is DTC P1121 or DTC P1635 also set?

--

Go to Step 6

Go to Step 4

4

Test for a faulty sensor ground circuit terminal connection at the manifold absolute pressure (MAP) sensor.

Was a problem found?

--

Go to Step  9

Go to Step  5

5

Test the MAP signal circuit between the MAP sensor connector and the PCM for an intermittent short to voltage.

Was a problem found?

--

Go to Step  10

Go to Step  8

6

Test for an intermittent short to voltage in the following circuit(s):

    • The 5 volt reference A circuit between the PCM and the TP, MAP, and/or EGR sensors.
    • The MAP sensor signal circuit.
    • The EGR pintle position signal circuit.
    • The TP sensor signal.

Was a problem found?

--

Go to Step  10

Go to Step  7

7

Test for a faulty sensor ground circuit terminal connection at the PCM.

Was a problem found?

--

Go to Step  9

Go to Step  8

8

Test for an intermittent open in the sensor ground circuit.

Was a problem found?

--

Go to Step  10

Go to Diagnostic Aids

9

Replace the malfunctioning harness connector terminal for the sensor ground circuit. Refer to Connector Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 11

--

10

Locate and repair an intermittent open/short circuit in the wiring harness as necessary. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

--

Go to Step 11

--

11

  1. Review and record the scan tool Fail Records data.
  2. Clear any DTCs.
  3. Operate the vehicle within the Fail Records conditions as noted.
  4. Use the scan tool in order to monitor the Specific DTC info for DTC P1106.

Does the scan tool indicate DTC P1106 Failed This Ign?

--

Go to Step 2

System OK