Hummer H2. Manual - part 1671

DTC P1107 

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: 

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5-volt reference circuit  

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Low reference circuit  

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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 low, DTC P1107 sets. 

Conditions for Running the DTC 

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The ignition is ON.  

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DTCs P0068, P0120, P0220, P1125, P1516, P2101, P2108, P2120, P2121, P2125, P2135 are not set.  

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The throttle angle is more than 0 percent when the engine speed is less than 800 RPM. 

OR 

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The throttle angle is more than 12.5 percent when the engine speed is more than 800 RPM.  

Conditions for Setting the DTC 

The PCM detects that the MAP sensor voltage is intermittently less than 0.10 volt. 

Action Taken When the DTC Sets 

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The control module stores the DTC information into memory when the diagnostic runs and fails.  

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The malfunction indicator lamp (MIL) will not illuminate.  

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The control module records the operating conditions at the time the diagnostic fails. The control module 
stores this information in the Failure Records.  

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The driver information center, if equipped, may display a message.  

Conditions for Clearing the DTC 

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0507 (TAC) To DTC U0107) - 4.8L, 5.3L, and 6.0L - 

Hummer H2

  

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A current DTC Last Test Failed clears when the diagnostic runs and passes.  

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A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other 
non-emission related diagnostic.  

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Clear the DTC with a scan tool.  

Test Description 

The numbers below refer to the step numbers on the diagnostic table. 

3: This step attempts to pinpoint the location of the intermittent fault.  

DTC P1107 

Step

Action

Yes

No

Schematic Reference:Engine Controls Schematics 
Connector End View Reference:Engine Controls Connector End Views or Powertrain Control 
Module (PCM) Connector End Views

1

Did you perform the Diagnostic System Check - Engine 
Controls?

Go to Step 2

Go to Diagnostic 

System Check - 

Engine Controls

2

1. Start the engine.  

2. Monitor the diagnostic trouble code (DTC) 

information with the scan tool.  

Is DTC P0107 or P0641 also set?

Go to Diagnostic 

Trouble Code 

(DTC) List

Go to Step 3

3

1. Turn OFF the ignition.  

2. Turn ON the ignition, with the engine OFF.  

3. Observe the MAP sensor parameter with the scan 

tool.  

4. Attempt to induce the fault that set the DTC by 

manipulating the following items: 

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The manifold absolute pressure (MAP) sensor 
wiring harness  

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The MAP sensor electrical connector  

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The powertrain control module (PCM) 
connector  

Refer to Inducing Intermittent Fault Conditions in 
Wiring Systems and Intermittent Conditions .Is the MAP 
sensor voltage affected during any part of the test?

Go to Step 4

Go to Step 8

4

Test the 5-volt reference circuit between the PCM and the 
MAP sensor for an open. Refer to Circuit Testing and 
Wiring Repairs in Wiring Systems. 
Did you find and correct the condition?

Go to Step 8

Go to Step 5

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0507 (TAC) To DTC U0107) - 4.8L, 5.3L, and 6.0L - 

Hummer H2

  

DTC P1111 

Circuit Description 

The intake air temperature (IAT) sensor is a variable resistor. The IAT sensor has a signal circuit and a low 
reference circuit. The IAT sensor measures the temperature of the air entering the engine. The powertrain 
control module (PCM) supplies 5 volts to the IAT signal circuit and a ground for the IAT low reference circuit. 
When the IAT sensor is cold, the sensor resistance is high. When the air temperature increases, the sensor 
resistance decreases. With high sensor resistance, the PCM detects a high voltage on the IAT signal circuit. 
With lower sensor resistance, the PCM detects a lower voltage on the IAT signal circuit. If the PCM detects an 
intermittent high IAT signal voltage, indicating a low temperature, DTC P1111 sets. 

Conditions for Running the DTC 

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DTCs P0101, P0102, P0103, P0113 are not set.  

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The engine run time is more than 120 seconds.  

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The ECT sensor parameter is more than 60°C (140°F). 

5

Test the MAP sensor signal circuit between the PCM and 
the MAP sensor for an intermittent short to ground or 
open. Refer to Circuit Testing and Wiring Repairs in 
Wiring Systems. 
Did you find and correct the condition?

Go to Step 8

Go to Step 6

6

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 8

Go to Step 7

7

Test for an intermittent and for a poor connection at the 
PCM. Refer to Testing for Intermittent Conditions and 
Poor Connections and Connector Repairs in Wiring 
Systems. 
Did you complete the action?

Go to Step 8

-

8

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 9

9

Observe the Capture Info with a scan tool. 
Are there any DTCs that have not been diagnosed?

Go to Diagnostic 

Trouble Code 

(DTC) List

System OK

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0507 (TAC) To DTC U0107) - 4.8L, 5.3L, and 6.0L - 

Hummer H2

  

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The vehicle speed is less than 11 km/h (7 mph).  

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The mass air flow is less than 15 g/s.  

Conditions for Setting the DTC 

The PCM detects that the IAT sensor parameter is less than -38°C (-36°F) intermittently for a calibrated amount 
of time. 

Action Taken When the DTC Sets 

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The control module stores the DTC information into memory when the diagnostic runs and fails.  

z

The malfunction indicator lamp (MIL) will not illuminate.  

z

The control module records the operating conditions at the time the diagnostic fails. The control module 
stores this information in the Failure Records.  

z

The driver information center, if equipped, may display a message.  

Conditions for Clearing the DTC 

z

A current DTC Last Test Failed clears when the diagnostic runs and passes.  

z

A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other 
non-emission related diagnostic.  

z

Clear the DTC with a scan tool.  

Diagnostic Aids 

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An IAT sensor or PCM which is intermittently shorted, open, or skewed is possible, yet very unlikely.  

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A skewed sensor could result in poor driveability conditions.  

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If an intermittent condition is suspected, refer to Intermittent Conditions .  

DTC P1111 

Step

Action

Value

(s)

Yes

No

Schematic Reference: Engine Controls Schematics 
Connector End View Reference: Powertrain Control Module (PCM) Connector End Views or 
Engine Controls Connector End Views

1

Did you perform the Diagnostic System Check-
Engine Controls?

-

Go to Step 2

Go to Diagnostic 

System Check - 

Engine Controls

2

Observe the DTC Information with a scan tool. 
Is DTC P0113 set?

-

Go to DTC 

P0113

Go to Step 3

3

Test for an intermittent and for a poor connection at 
the IAT sensor. Refer to Testing for Intermittent 
Conditions and Poor Connections and Connector 
Repairs in Wiring Systems. 

-

 

2004 Hummer H2 

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0507 (TAC) To DTC U0107) - 4.8L, 5.3L, and 6.0L - 

Hummer H2