Hummer H2. Manual - part 323

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 interior backlighting is 
inoperative. 
Does the interior backlighting operate 
normally?

Go to Testing for 

Intermittent Conditions 

and Poor Connections in 

Wiring Systems

Go to Step 3

3

Are all of the interior backlighting lamps 
inoperative?

Go to Step 5

Go to Step 4

4

Test for an open or high resistance in the 
following circuits of the inoperative lamp. Refer 
to Circuit Testing and Wiring Repairs in 
Wiring Systems. 

z

The instrument panel lamps dimming 
control  

z

The LED dimming supply  

z

The ground  

 
Did you find and correct a condition?

Go to Step 13

Go to Step 8

5

Is the TBC 2A Fuse in the I/P fuse block open?

Go to Step 6

Go to Step 7

6

Test the battery positive voltage circuit of the 
BCM for a short to ground. Refer to Circuit 
Testing and Wiring Repairs in Wiring 
Systems. 
Did you find and correct the condition?

Go to Step 13

Go to Step 10

7

Test for the following conditions. Refer to 
Circuit Testing and Wiring Repairs in Wiring 
Systems. 

z

Short to voltage in the dimmer 
potentiometer low reference circuit of the 
BCM.  

z

High resistance or an open in the LED 
dimming signal circuit of the BCM.  

z

Short to ground in the LED dimming 
signal circuit of the BCM.  

 
Did you find and correct the condition?

Go to Step 13

Go to Step 9

8

Inspect for poor connections at the harness 
connector of the affected lamp. Refer to Circuit 
Testing and Wiring Repairs in Wiring 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

  

INSTRUMENT PANEL (I/P) COMPARTMENT LAMP INOPERATIVE 

Instrument Panel (I/P) Compartment Lamp Inoperative 

Systems. 
Did you find and correct the condition?

Go to Step 13

Go to Step 11

9

Inspect for poor connections at the harness 
connector of the body control module. 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

10

Repair the controls illumination lamps dimming 
control circuit for a short to ground. Refer to 
Wiring Repairs in Wiring Systems. 
Did you complete the repair?

Go to Step 13

-

11

Replace the affected lamp or internal lamp 
component. 
Did you complete the replacement?

Go to Step 13

-

12 Replace the body control module (BCM). Refer 

to Body Control Module Replacement in 
Body Control System.Did you complete the 
replacement?

IMPORTANT:

Perform the setup procedure for the BCM.

Go to Step 13

-

13

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:Interior Lights SchematicsBody Control System 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 Diagnostic System 
Check?

Go to Step 2

Go to Diagnostic 

System Check - 

Lighting Systems

2

1. Open the instrument panel (I/P) compartment.  

2. Depress the I/P compartment lamp switch.  

Does the system operate normally?

Go to Testing for 

Electrical 

Intermittents in 

Wiring Systems

Go to Step 3

3

Are all of the reading, visor and I/P compartment 
lamps inoperative?

Go to Step 4

Go to Step 6

4

Is the TBC 2C Fuse in the I/P fuse block open?

Go to Step 5

Go to Step 6

5

Test the battery positive voltage circuit of the BCM for 
a short to ground. Refer to Circuit Testing and 
Wiring Repairs in Wiring Systems. 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

  

INSTRUMENT PANEL (I/P) COMPARTMENT LAMP ALWAYS ON 

Instrument Panel (I/P) Compartment Lamp Always On 

Did you find and correct the condition?

Go to Step 14

Go to Step 11

6

Remove and inspect the bulb. 
Is the bulb open?

Go to Step 9

Go to Step 7

7

Test the courtesy lamp supply voltage circuit of the I/P 
compartment 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 14

Go to Step 8

8

Test the courtesy lamp ground circuit of the I/P 
compartment 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 14

Go to Step 10

9

Inspect for poor connections at the harness connector 
of the I/P compartment bulb. 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 14

Go to Step 12

10

Inspect for poor connections at the harness connector 
of the I/P compartment assembly. 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 14

Go to Step 13

11

Repair the inadvertent power supply voltage circuit for 
a short to ground. Refer to Wiring Repairs in Wiring 
Systems. 
Did you complete the repair?

Go to Step 14

-

12

Replace the bulb. 
Did you complete the replacement?

Go to Step 14

-

13

Replace the I/P compartment lamp assembly. Refer to 
Instrument Panel (I/P) Compartment Lamp Switch 
Replacement . 
Did you complete the replacement?

Go to Step 14

-

14

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

System OK

Go to Step 3

Step

Action

Yes

No

1

Did you review the Interior Lighting Systems Description 
and Operation and perform the necessary inspections?

Go to 

Step 2

Go to Interior Lighting 

Systems Description and 

Operation

2

Inspect the door closure operation to ensure that the 
switch is completely deactivated when closed. 

Go to 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

  

OFF-ROAD LAMPS ALWAYS ON 

Off-Road Lamps Always On 

Was a problem found?

Step 3

Go to Step 4

3

Adjust the I/P compartment door for proper closure and 
switch deactivation. 
Did you complete the repair?

Go to 

Step 5

-

4

Replace the I/P compartment lamp/switch assembly. 
Refer toInstrument Panel (I/P) Compartment Lamp 
Switch Replacement . 
Did you complete the replacement?

Go to 

Step 5

-

5

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

Place the off-road lamps switch in the ON and then 
the OFF positions. 
Does the system operate normally?

Go to Testing for 

Intermittent Conditions 

and Poor Connections in 

Wiring Systems

Go to Step 3

3

Disconnect the off-road lamps switch. 
Do the off-road lamps turn OFF?

Go to Step 6

Go to Step 4

4

1. Reconnect the off-road lamps switch.  

2. Disconnect both off-road lamps relays, 

noting which one turns off the lamps.  

Do the off-road lamps turn OFF?

Go to Step 5

Go to Step 8

5

Test the off-road lamps relay control circuit of the 
off-road lamps switch 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 11

Go to Step 7

6

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. 
Did you find and correct the condition?

Go to Step 11

Go to Step 9

Inspect for poor connections at the harness 

 

2004 Hummer H2 

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2