Hummer H2. Manual - part 1118

Circuit Description

The powertrain control module (PCM) continuously monitors that the system voltage stays within the proper
range. If the PCM detects an excessively high system voltage, DTC P0563 will set. A high voltage condition
may cause a stalling condition or other driveability concerns.

Conditions for Running the DTC

The engine run time is more than 20 seconds.

Engine running above 1200 RPM.

Vehicle speed above 8 km/h (5 mph).

Conditions for Setting the DTC

The PCM senses the system voltage is above 19 volts.

All of the conditions are present for 5 seconds.

Action Taken When the DTC Sets

The PCM stores DTC P0563 in the PCM memory when the diagnostic runs and fails.

The PCM will record the operating conditions at the time the diagnostic fails. The PCM stores this
information in Failure Records.

The PCM disables most outputs.

The transmission defaults to a predetermined gear.

The torque converter clutch (TCC) operation is inhibited.

The instrument panel cluster (IPC) displays a message.

The malfunction indicator lamp (MIL) will not illuminate.

Conditions for Clearing the DTC

The Conditions for Setting the DTC are no longer present.

A history DTC will clear after 40 malfunction free ignition cycles.

The Powertrain Control Module (PCM) receives the clear code command from the scan tool.

DTC P0563

Step

Action

Value

(s)

Yes

Schematic Reference:Starting and Charging Schematics
Connector End View Reference: Engine Electrical Connector End Views

Did you perform the Engine Electrical Diagnostic
System Check?

Go to

Step 2

Go to Diagnostic System

Check - Engine

Electrical

1. Turn OFF all the accessories.

2004 Hummer H2

2004 ELECTRICAL Engine Electrical - Hummer H2

DTC P0615

Circuit Description

The PCM uses Output Driver Modules (ODMs) to control many functions of the engine. The ODMs supply the
ground path for the PCM controlled device when the PCM commands the device ON. Each ODM is able to
control several outputs. The PCM monitors the ODMs for circuit conditions that are incorrect for the
commanded state of the ODM. If the PCM detects an improper circuit condition in the ODM that controls the
starter relay, DTC P0615 will set.

Conditions for Running the DTC

System voltage is between 8-16 volts.

Conditions for Setting the DTC

The PCM detects an improper voltage level on the output circuit that controls the starter relay.

The condition exists for at least 2 seconds.

Action Taken When the DTC Sets

The PCM will not illuminate the Malfunction Indicator Lamp (MIL).

2. Measure the battery voltage at the battery using

the DMM.

3. Operate the engine speed above 2000 RPM.

Is the battery voltage less than the specified value?

19 V

Go to

Step 4

Go to Step 3

Replace the generator. Refer to Generator
Replacement .
Is the action complete?

Go to

Step 5

Replace the PCM. Refer to Powertrain Control
Module (PCM) Replacement in Engine Controls.Is
the action complete?

IMPORTANT:

The replacement PCM must be programmed.

Go to

Step 5

1. Select the Diagnostic Trouble Code (DTC)

option and the Clear DTC Information option
using the scan tool.

2. Operate the vehicle within the Conditions for

Running the DTC as specified in the supporting
text, if applicable.

Does the DTC reset?

Go to

Step 2

System OK

2004 Hummer H2

2004 ELECTRICAL Engine Electrical - Hummer H2

The PCM will store the conditions present when the DTC set as Fail Records data only.

Conditions for Clearing the MIL/DTC

The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.

The DTC can be cleared by using the scan tool Clear DTC Information function.

Diagnostic Aids

Ignition system DTCs set with the ignition switch in the START position if the starter relay or the starter is
inoperative. When the PCM enables starter operation, the PCM also initiates the diagnostic test routines for
DTC P0335. If a condition exists which prevents the engine from cranking, the PCM will not receive signal
input from the CKP and CMP sensors, and the DTCs will set.

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

Test Description

The number(s) below refer to the step number(s) on the diagnostic table.

2: Listen for an audible click when the Start 1 relay operates. Turn the ignition switch back and forth
from the ON to START positions. Repeat this as necessary.

3: Tests for voltage at the coil side of the Start 1 relay. The PCM IGN fuse supplies power to the coil side
of the Start 1 relay.

4: Verifies that the PCM is providing ground to the Start 1 relay.

5: Tests if ground is constantly being applied to the Start 1 relay.

DTC P0615

Step

Action

Yes

Schematic Reference:Starting and Charging Schematics
Connector End View Reference: Engine Electrical Connector End Views

Did you perform the Engine Electrical
Diagnostic System Check?

Go to Step 2

Go to Diagnostic

System Check -

Engine Electrical

1. Install a scan tool.

2. Turn ON the ignition, with the engine

OFF.

3. Turn the ignition back and forth from the

ON to START positions.

Does the Start 1 relay turn ON and OFF with
each command?

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

Go to Step 3

1. Turn OFF the ignition.

2004 Hummer H2

2004 ELECTRICAL Engine Electrical - Hummer H2

2. Disconnect the Start 1 relay.

3. Turn ON the ignition, with the engine

OFF.

4. Probe the battery positive voltage of the

Start 1 relay coil circuit with a test lamp
that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 4

Go to Step 8

1. Connect a test lamp between the control

circuit of the Start 1 relay and the battery
positive voltage of the Start 1 relay coil
circuit.

2. Turn the ignition back and forth from the

ON to START positions.

Does the test lamp turn ON and OFF with each
command?

Go to Step 6

Go to Step 5

Test the control circuit of the Start 1 relay for a
short to voltage or an open. Refer to Circuit
Testing and Wiring Repairs in Wiring
Systems.
Did you find and correct the condition?

Go to Step 11

Go to Step 7

Inspect for poor connections at the Start 1 relay.
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 11

Go to Step 9

Inspect for poor connections 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 11

Go to Step 10

Repair the battery positive voltage circuit of the
Start 1 relay. Refer to Connector Repairs in
Wiring Systems.
Did you complete the repair?

Go to Step 11

Replace the Start 1 relay. Refer to Relay
Replacement (Within an Electrical Center) or
Relay Replacement (Attached to Wire
Harness) in Wiring Systems.
Did you complete the replacement?

Go to Step 11

IMPORTANT:

The replacement PCM must be programmed.

2004 Hummer H2

2004 ELECTRICAL Engine Electrical - Hummer H2

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