Hummer H3. Manual — part 1411

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to
Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the
symptom:

Backup Lamps Always On

Backup Lamps Inoperative

Clearance Lamps Inoperative

Courtesy Lamps Always On

Courtesy Lamps Inoperative

Daytime Running Lamps (DRL) Always On

Daytime Running Lamps (DRL) Inoperative

Daytime Running Lamps (DRL) On with Park Brake Applied

Fog Lamp Indicator Inoperative

Fog Lamps Always On

Fog Lamps Inoperative

Rear Fog Lamps Always On

Rear Fog Lamps Inoperative

Hazard Lamps Always On

Hazard Lamps Inoperative

Headlamp Low or High Beams Always On

Headlamps Inoperative - High Beams

Headlamps Inoperative - Low Beams

Low and High Beams Headlamps Inoperative

Headlamps Flash to Pass Inoperative

Headlight Leveling Inoperative

High Beam Indicator Always On

High Beam Indicator Inoperative

Interior Backlighting Does Not Dim

Interior Backlighting Inoperative

License Lamps Inoperative

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

Off-Road Lamps Always On

Off-Road Lamps Inoperative

Marker Lamps Inoperative

Park Lamps Inoperative

Park, License and Tail Lamps Always On

Park, License and Tail Lamps Inoperative

Position Lamps Malfunction

Stop Lamps Always On

Stop Lamps Inoperative

Tail Lamps Inoperative

Turn Signal Lamps and/or Indicators Always On or Flashing

Turn Signal Lamps and/or Indicators Inoperative

Vanity Mirror Lamp(s) Inoperative

BACKUP LAMPS ALWAYS ON

Backup Lamps Always On

Step

Action

Yes

No

Schematic Reference: Exterior Lights Schematics
Connector End View Reference: Lighting Systems Connector End Views, Automatic
Transmission Related Connector End Views or Manual Transmission Connector
End Views

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to Step 2

Go to

Diagnostic

System Check -

Vehicle

2

1. Block the rear wheels.

2. Turn ON the ignition, with the engine

OFF.

3. Place the gear selector in PARK or the

shifter in Neutral.

Do the backup lamps illuminate?

Go to Step 3

Go to Testing

for

Intermittent

Conditions and

Poor

Connections

Disconnect the park/neutral position (PNP)
switch, if equipped with a automatic

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

BACKUP LAMPS INOPERATIVE

Backup Lamps Inoperative

3

transmission or the backup lamp switch, if
equipped with a manual transmission.
Do the backup lamps remain illuminated?

Go to Step 4

Go to Step 5

4

Repair the short to battery positive voltage
in the backup lamps supply voltage circuit.
Refer to Circuit Testing and Wiring
Repairs .
Did you complete the repair?

Go to Step 6

-

5

Adjust or replace the PNP switch or backup
lamp switch. Refer to Park/Neutral
Backup Switch Adjustment and
Park/Neutral Backup Switch
Replacement or Backup Lamp Switch
Replacement .
Did you complete the repair?

Go to Step 6

-

6

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, Automatic
Transmission Related Connector End Views or Manual Transmission Connector
End Views

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to Step 2

Go to

Diagnostic

System Check -

Vehicle

2

1. Turn ON the ignition, with the engine

OFF.

2. Block the rear wheels.

3. Place the gear selector or shifter in the

REVERSE position.

Do both backup lamps illuminate?

Go to Testing

for

Intermittent

Conditions

and Poor

Connections

Go to Step 3

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

3

Is only one lamp inoperative?

Go to Step 4

Go to Step 5

4

Connect a test lamp between the backup
lamp supply voltage circuit and the ground
circuit of the socket.
Does the test lamp illuminate?

Go to Step 9

Go to Step 8

5

1. Turn OFF the ignition.

2. Connect a 15-amp fused jumper wire at

the connector between the ignition
positive voltage circuit and the backup
lamp supply voltage circuit of the
park/neutral position (PNP) switch, if
equipped with an automatic
transmission or the backup lamp
switch, if equipped with a manual
transmission.

3. Turn ON the ignition, with the engine

OFF.

Do the backup lamps illuminate?

Go to Step 6

Go to Step 7

6

Inspect for poor connections at the harness
connector of the PNP switch or backup lamp
switch. Refer to Testing for Intermittent
Conditions and Poor Connections and
Connector Repairs .
Did you find and correct the condition?

Go to Step 11 Go to Step 10

7

Repair one of the following conditions.
Refer to Circuit Testing and Wiring
Repairs .

The open, high resistance or short to
ground in the ignition positive voltage
circuit or the backup lamps supply
voltage circuit

The open or high resistance in the
ground circuit

Did you complete the repair?

Go to Step 11

-

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3