Hummer H2. Manual — part 1522

12

DMM. Note the measurement as "Supply voltage".

3. Connect a test lamp and a DMM in series between

the 5-volt reference circuit and the low reference
circuit of the MAP sensor at the harness connector.

4. Measure the amperage with the DMM. Note the

measurement as "Amperage".

Is the amperage equal to the specified value?

0 mA

Go to Step 16

Go to Step 13

13

1. Remove the DMM from the circuit.

2. Connect the test lamp between the 5-volt reference

circuit and the low reference circuit of the MAP
sensor, at the harness connector.

3. Measure the voltage from the 5-volt reference

circuit at the test lamp to a good ground, with the
DMM. Note the measurement as "Load voltage
drop".

4. Subtract the "Load voltage drop" from the "Supply

voltage". Note the result as "Supply voltage drop".

5. Divide the "Supply voltage drop" by the

"Amperage".

Is the result more than the specified value?

IMPORTANT:

Before any calculations are performed, ensure
that all measurements are converted to like
units, for example, volts/amps or
millivolts/milliamps.

5 ohm

Go to Step 15

Go to Step 14

14

1. Measure the voltage from the low reference circuit

of the MAP sensor at the test lamp to a good
ground, with the DMM. Note the result as "Low
reference voltage drop".

2. Divide the "Low reference voltage drop" by the

"Amperage".

Is the result more than the specified value?

IMPORTANT:

Before any calculations are performed, ensure
that all measurements are converted to like
units, for example, volts/amps or
millivolts/milliamps.

5 ohm

Go to Step 17

Go to Step 19

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0068 To DTC P0141/P0161) - 4.8L, 5.3L, and 6.0L -

Hummer H2

DTC P0107

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:

15

Test the 5-volt reference circuit between the powertrain
control module (PCM) and the MAP sensor for high
resistance. Refer to Circuit Testing and Wiring Repairs
in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 21

Go to Step 18

16

Test the low 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 21

Go to Step 18

17

Test the low reference circuit between the PCM and the
MAP sensor for high resistance. Refer to Circuit
Testing and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 21

Go to Step 18

18

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 find and correct the condition?

-

Go to Step 21

Go to Step 20

19

Replace the MAP sensor. Refer to Manifold Absolute
Pressure (MAP) Sensor Replacement .
Did you complete the replacement?

-

Go to Step 21

-

20

Replace the PCM. Refer to Powertrain Control Module
(PCM) Replacement .
Did you complete the replacement?

-

Go to Step 21

-

21

1. Clear the DTCs with the 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 22

22

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 P0068 To DTC P0141/P0161) - 4.8L, 5.3L, and 6.0L -

Hummer H2

z

5-volt reference circuit

z

Low reference circuit

z

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 excessively low, DTC P0107 sets.

Conditions for Running the DTC

z

The ignition is ON.

z

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

z

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

OR

z

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 less than 0.10 volt for more than 4 seconds.

Action Taken When the DTC Sets

z

The control module illuminates the malfunction indicator lamp (MIL) on the second consecutive ignition
cycle that the diagnostic runs and fails.

z

The control module records the operating conditions at the time the diagnostic fails. The first time the
diagnostic fails, the control module stores this information in the Failure Records. If the diagnostic
reports a failure on the second consecutive ignition cycle, the control module records the operating
conditions at the time of the failure. The control module writes the operating conditions to the Freeze
Frame and updates the Failure Records.

Conditions for Clearing the MIL/DTC

z

The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles
that the diagnostic runs and does not fail.

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

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0068 To DTC P0141/P0161) - 4.8L, 5.3L, and 6.0L -

Hummer H2

emission related diagnostic.

z

Clear the MIL and the DTC with a scan tool.

DTC P0107

Step

Action

Values

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. Turn ON the ignition, with the engine OFF.

2. Monitor the Diagnostic Trouble Code (DTC)

Information with the scan tool.

Is DTC P0641 also set?

-

Go to DTC

P0641

Go to Step 3

3

Observe the MAP sensor parameter with the scan
tool.
Is the voltage is less than the specified value?

0.1 V

Go to Step 5

Go to Step 4

4

1. Observe the Freeze Frame/Failure Records for

this DTC.

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.

Does the DTC fail this ignition?

-

Go to Step 5

Go to Intermittent

Conditions

5

Test for an intermittent and for a poor connection at
the manifold absolute pressure (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 13

Go to Step 6

6

1. Turn OFF the ignition.

2. Disconnect the MAP sensor electrical

connector.

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

4. Measure the voltage from the 5-volt reference

circuit of the MAP sensor to a good ground,
with a DMM.

4.8 V

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0068 To DTC P0141/P0161) - 4.8L, 5.3L, and 6.0L -

Hummer H2