Hummer H2. Manual - part 1553

DTC P0336

Circuit Description

The crankshaft position (CKP) sensor signal indicates the crankshaft speed and position. The CKP sensor
circuits are connected directly to the powertrain control module (PCM) and consists of the following circuits:

The 12-volt reference circuit

The low reference circuit

The CKP sensor signal circuit

If the PCM detects that the CKP sensor signal is inconsistent for 2 seconds, DTC P0336 sets.

Conditions for Running the DTC

The engine is cranking or running.

Conditions for Setting the DTC

The PCM detects that the CKP sensor signal is inconsistent for 2 seconds.

Action Taken When the DTC Sets

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

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

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 17

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 P0171/P0174 To DTC P0507 (TAC)) - 4.8L, 5.3L, and

6.0L - Hummer H2

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

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
emission related diagnostic.

Clear the MIL and the DTC with a scan tool.

DTC P0336

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. 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.

Did the DTC fail this ignition?

IMPORTANT:

If DTC P0335 is also set, diagnose DTC P0335 before
proceeding with this DTC.

Go to Step 3

Go to Intermittent

Conditions

Inspect all of the crankshaft position sensor (CKP) circuits
for the following conditions:

Wiring routed too closely to secondary ignition
wires or components

Wiring routed too closely to after-market add-on
electrical equipment

Wiring routed to closely to solenoids, relays, and
motors

Electromagnetic interference in the CKP sensor
circuits

Did you find and correct the condition?

Go to Step 12

Go to Step 4

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0171/P0174 To DTC P0507 (TAC)) - 4.8L, 5.3L, and

6.0L - Hummer H2

Test the 12-volt reference circuit for an intermittent
condition or shorted to other circuits. Refer to Testing for
Electrical Intermittents and Inducing Intermittent
Fault Conditions in Wiring Systems.
Did you find and correct the condition?

Go to Step 12

Go to Step 5

Test the low reference circuit for an intermittent condition.
Refer to Testing for Electrical Intermittents and
Inducing Intermittent Fault Conditions in Wiring
Systems.
Did you find and correct the condition?

Go to Step 12

Go to Step 6

Test the CKP sensor signal circuit for an intermittent
condition. Refer to Testing for Electrical Intermittents
and Inducing Intermittent Fault Conditions in Wiring
Systems.
Did you find and correct the condition?

Go to Step 12

Go to Step 7

Test for an intermittent and for a poor connection at the
CKP sensor. Refer to Testing for Intermittent
Conditions and Poor Connections and Wiring Repairs
in Wiring Systems.
Did you find and correct the condition?

Go to Step 12

Go to Step 8

Test for an intermittent and for a poor connection at the
powertrain control module (PCM). Refer to Testing for
Intermittent Conditions and Poor Connections and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 12

Go to Step 9

1. Remove the CKP sensor. Refer to Crankshaft

Position (CKP) Sensor Replacement .

2. Inspect the CKP sensor for the following conditions:

Physical damage

Improper installation

Excessive play or looseness

Excessive air gap between the CKP sensor and
the reluctor wheel

Foreign material passing between the CKP
sensor and the reluctor wheel

Insufficient fuel

Did you find and correct the condition?

Go to Step 12

Go to Step 10

Inspect the reluctor wheel for the following conditions:

Physical damage

Improper installation

Excessive endplay or looseness

2004 Hummer H2

2004 ENGINE PERFORMANCE Engine Controls Diagnosis (DTC P0171/P0174 To DTC P0507 (TAC)) - 4.8L, 5.3L, and

6.0L - Hummer H2

DTC P0341

Circuit Description

The camshaft position (CMP) sensor works in conjunction with a 1 X reluctor wheel on the camshaft. The
powertrain control module (PCM) provides a 12 volt reference to the CMP sensor as well as a low reference
and a signal circuit.

As the camshaft rotates, the reluctor wheel interrupts a magnetic field produced by a magnet within the sensor.
The sensors internal circuitry detects this and produces a signal which the PCM reads.

The CMP sensor 1 X signal is used by the PCM to determine if the cylinder at top dead center (TDC) is on the
firing stroke or the exhaust stroke. The PCM can determine TDC for all cylinders by using the CKP sensor 24 X
signal alone. The engine will start without a CMP signal as long as the PCM receives the CKP sensor 24 X
signal. A slightly longer cranking time may be a symptom of this condition. The system attempts
synchronization and looks for an increase in engine speed indicating that the engine started. If the PCM does
not detect an increase in engine speed, the PCM assumes that the PCM incorrectly synchronized to the exhaust
stroke and re-syncs to the opposite cam position. If the PCM detects that a CMP to CKP mis-match has
occurred DTC P0341 sets.

Conditions for Running the DTC

The engine is running and the engine speed is less than 4,000 RPM.

Conditions for Setting the DTC

Refer to Crankshaft and Bearings Cleaning and
Inspection in Engine Mechanical.
Did you find and correct the condition?

Go to Step 12

Go to Step 11

Replace the CKP sensor. Refer to Crankshaft Position
(CKP) Sensor Replacement .
Did you complete the replacement?

Go to Step 12

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 13

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 P0171/P0174 To DTC P0507 (TAC)) - 4.8L, 5.3L, and

6.0L - Hummer H2

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