Hummer H2. Manual — part 324

OFF-ROAD LAMPS INOPERATIVE

Off-Road Lamps Inoperative

7

connector of the off-road lamps 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 10

8

Repair the off-road lamps supply voltage circuit for
a short to voltage. Refer to Wiring Repairs in
Wiring Systems.
Did you complete the repair?

Go to Step 11

-

9

Replace the off-road lamps switch. Refer to Switch
Replacement - Off-Road Lamps
Did you complete the replacement?

Go to Step 11

-

10

Replace the appropriate off-road lamps relay. Refer
to Relay Replacement (Within an Electrical
Center)Relay Replacement (Attached to Wire
Harness) in Wiring Systems.
Did you complete the repair?

Go to Step 11

-

11

Operate the system in order to verify the repair.
Did you correct the condition?

System OK

Go to Step 3

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics
Connector End View Reference: Lighting Systems Connector End Views or Body Control System
Connector End Views in Body Control System.

1

Did you perform the Lighting Systems Diagnostic
System Check?

Go to Step 2

Go to Diagnostic

System Check -

Lighting Systems

2

Verify that the off-road lamps are inoperative.
Do the off-road lamps operate normally?

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

Go to Step 3

3

Is only one off-road lamp inoperative?

Go to Step 4

Go to Step 6

4

Test the supply voltage circuit of the inoperative
lamp for high resistance, short to ground or 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 5

5

Test the ground circuit of the inoperative lamp for
high resistance, or 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 13

Connect a test lamp between the battery positive

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

6

voltage circuit of the off-road lamps switch, and a
good ground.
Does the test lamp illuminate?

Go to Step 7

Go to Step 16

7

Connect a 3 amp fused jumper wire between the
battery positive circuit and the off-road lamp relay
control circuit of the off-road lamps switch.
Do the off-road lamps illuminate?

Go to Step 15

Go to Step 8

8

Connect a 3 amp fused jumper wire between the
battery positive circuit and the off-road lamp
supply voltage circuit of the off-road lamps relay.
Do the off-road lamps illuminate?

Go to Step 9

Go to Step 11

9

Test the off-road lamp relay control circuit of the
off-road lamps switch for high resistance, short to
ground or 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 10

10

Test the ground circuit of the off-road lamps relay
for high resistance, or an open. Refer to Circuit
Testing andWiring Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 21

Go to Step 11

11

Test the battery positive voltage circuit of the off-
road lamps relay for high resistance, or 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 12

12

Test the ground circuit of the off-road lamps for
high resistance, or 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 17

13

Inspect for poor connections at the harness
connector of the off-road lamp. 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 18

14

Inspect for poor connections at the harness
connector of the off-road lamps 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 21

Go to Step 19

15

Inspect for poor connections at the harness
connector of the off-road lamps switch. Refer to
Testing for Intermittent Conditions and Poor
Connections and Connector Repairs in Wiring
Systems.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

PARK, LICENSE, AND TAIL LAMPS ALWAYS ON

Park, License, and Tail Lamps Always On

Did you find and correct the condition?

Go to Step 21

Go to Step 20

16

Repair the battery positive voltage circuit of the
off-road lamps switch. Refer to Wiring Repairs
in Wiring Systems.
Did you complete the repair?

Go to Step 21

-

17

Repair the supply voltage circuit of the off-road
lamps. Refer to Wiring Repairs in Wiring
Systems.
Did you complete the repair?

Go to Step 21

-

18

Replace the inoperative off-road lamp. Refer to
Off-Road Lamp Replacement - Roof
Did you complete the replacement?

Go to Step 21

-

19

Replace the inoperative off-road lamps relay.
Refer to Relay Replacement (Within an
Electrical Center)Relay Replacement
(Attached to Wire Harness) in Wiring Systems.
Did you complete the replacement?

Go to Step 21

-

20

Replace the off-road lamps switch. Refer to
Switch Replacement - Off-Road Lamps
Did you complete the replacement?

Go to Step 14

-

21

Operate the system in order to verify the repair.
Did you correct the condition?

System OK

Go to Step 3

Step

Action

Yes

No

Schematic Reference:Exterior Lights Schematics
Connector End View Reference:Lighting Systems Connector End Views or Body Control System
Connector End Views in Body Control System

1

Did you perform the Lighting Systems
Diagnostic System Check?

Go to Step 2

Go to Diagnostic

System Check -

Lighting Systems

2

Verify that the park, license and tail lamps are
always ON.
Do the park, license and tail lamps operate
normally?

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

Go to Step 3

3

Remove the park lamp relay.
Do the park lamps turn OFF?

Go to Step 4

Go to Step 9

4

1. Ensure that the headlamp switch is in the

AUTO position and there is sufficient
light to the ambient light sensor.

2. Test for a ground signal at the park lamp

relay control circuit terminal in the

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

underhood fuse block. Refer to Circuit
Testing in Wiring Systems.

Was a ground signal present?

Go to Step 5

Go to Step 10

5

Use the scan tool to check the body control
module (BCM) parklamp switch input data.
Does the scan tool indicate a park lamps OFF
request signal?

Go to Step 8

Go to Step 6

6

Test for a short to ground in the park lamp
switch signal circuit. Refer to Circuit
TestingWiring Repairs in Wiring Systems.
Did you find and correct the condition?

Go to Step 13

Go to Step 7

7

Inspect for poor connections at the harness
connector of the headlamp switch. Refer to
Circuit Testing and Wiring Repairs in Wiring
Systems.
Did you find and correct the condition?

Go to Step 13

Go to Step 11

8

Inspect for poor connections at the harness
connector of the BCM. 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

9

Repair the short to voltage in one of the
following circuits:

z

Front park lamp supply voltage

z

Trailer park lamps supply voltage

z

Right rear park lamps supply voltage

z

Left rear park lamps supply voltage

z

Interior park lamps supply voltage

Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?

Go to Step 13

-

10

Replace the park lamp relay. Refer to Relay
Replacement (Within an Electrical Center)
Relay Replacement (Attached to Wire
Harness) in Wiring Systems.
Did you complete the repair?

Go to Step 13

-

11

Replace the headlamp switch. Refer to
Headlamp Switch Replacement .
Did you complete the repair?

Go to Step 13

-

IMPORTANT:

Perform the setup procedure for the BCM.

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2