Content .. 1568 1569 1570 1571 ..

Hummer H2. Manual - part 1570

2. Disconnect the fuel tank pressure (FTP)

sensor.

3. Measure the voltage from the 5-volt

reference circuit of the FTP sensor to a
good ground with a DMM. Refer to Circuit
Testing in Wiring Systems.

Is the voltage within the specified range?

4.8-5.2

Go to

Intermittent

Conditions

Go to Step 11

Is the voltage measured in step 3 more than the
specified value?

5.2 V

Go to Step 8

Go to Step 6

Monitor the DMM while disconnecting the FTP
sensor.
Does the voltage return to within the specified
range when the FTP is disconnected?

4.8-5.2

Go to Step 10

Go to Step 7

1. Turn OFF the ignition.

2. Disconnect the powertrain control module

(PCM).

3. Test the 5-volt reference circuit for a short

to ground or any sensor low reference
circuit. Refer to Circuit Testing and
Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 12

1. Turn OFF the ignition.

2. Disconnect the PCM.

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

4. Test all 5-volt reference circuits 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 13

Go to Step 9

Test the FTP sensor signal circuit 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 13

Go to Step 12

Replace the FTP sensor. Refer to Fuel Tank
Pressure Sensor Replacement .
Did you complete the replacement?

Go to Step 13

Replace the A/C pressure sensor. Refer to Air
Conditioning (A/C) Refrigerant Pressure
Sensor Replacement in HVAC.
Did you complete the replacement?

Go to Step 13

Replace the PCM. Refer to Powertrain Control

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 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.

Conditions for Running the DTC

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

The engine is running.

The throttle angle is less than 1 percent when the engine speed is less than 1,200 RPM.

Module (PCM) Replacement .
Did you complete the replacement?

Go to Step 13

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 14

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

The throttle angle is more than 20 percent when the engine speed is more than 1,200 RPM.

Conditions for Setting the DTC

The PCM detects that the MAP sensor voltage is intermittently more than 4.9 volts.

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.

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 P1106

Step

Action

Yes

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

Did you perform the Diagnostic System Check - Engine
Controls?

Go to Step 2

Go to Diagnostic

System Check -

Engine Controls

1. Start the engine.

2. Monitor the diagnostic trouble code (DTC)

information with the scan tool.

Is DTC P0108 or P0641 also set?

Go to Diagnostic

Trouble Code

(DTC) List

Go to Step 3

1. Observe the MAP sensor parameter with the scan tool.

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

2004 Hummer H2

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

Hummer H2

manipulating the following items:

The manifold absolute pressure (MAP) sensor
wiring harness

The MAP sensor electrical connector

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

Test the low reference circuit between the PCM and the
MAP sensor for an intermittent 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

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 in Wiring
Systems.Did you find and correct the condition?

IMPORTANT:

Disconnecting the PCM may eliminate the short during
testing.

Go to Step 8

Go to Step 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

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

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

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

Content .. 1568 1569 1570 1571 ..