Hummer H3. Manual — part 1418

12

Test for a short to ground in the headlamp
relay control circuit. Refer to Circuit
Testing and Electrical Center
Identification Views .
Did you find and correct a condition?

Go to Step 21

Go to Step 13

13

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

Go to Step 21

Go to Step 17

14

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

Go to Step 21

Go to Step 19

15

Repair the short to ground in the right or
left low or high beam headlamp ground
circuit. Refer to Circuit Testing and
Wiring Repairs .
Did you complete the repair?

Go to Step 21

-

16

Repair the short to voltage in the right or
left low beam headlamp supply voltage
circuit. Refer to Wiring Repairs .
Did you complete the repair?

Go to Step 21

-

17

Replace the BCM. Refer to Control
Module References for replacement, setup
and programming.
Did you complete the replacement?

Go to Step 21

-

18

Replace the headlamp relay. Refer to Relay
Replacement (Attached to Wire
Harness) or Relay Replacement (Within
an Electrical Center) .
Did you complete the repair?

Go to Step 21

-

19

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

Go to Step 21

-

20

Replace the turn signal/multifunction
switch. Refer to Turn Signal

-

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

HEADLAMPS INOPERATIVE - HIGH BEAMS

Headlamps Inoperative - High Beams

Multifunction Switch Replacement .
Did you complete the repair?

Go to Step 21

21

1. Use the scan tool in order to clear any

induced DTCs.

2. 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: Headlights/Daytime Running Lights (DRL) Schematics
Connector End View Reference: Lighting Systems Connector End Views or Data
Communication Connector End Views

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to Step 2

Go to
Diagnostic
System Check -
Vehicle

2

Verify that the high beam headlamps are
inoperative.
Do the high beam headlamps operate
normally?

Go to Testing
for Intermittent
Conditions and
Poor
Connections

Go to Step 3

3

Is only one high beam headlamp
inoperative?

Go to Step 4

Go to Step 5

4

1. Inspect the inoperative bulb for an

open filament and connector for poor
terminal contact and replace/repair as
necessary. Refer to Headlamp Bulb
Replacement or Wiring Repairs .

2. If the condition above does not exist,

repair the open, high resistance or
short to ground in the high beam
headlamp supply voltage circuit or
ground circuit to the inoperative
lamp. Refer to Circuit Testing

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

andWiring Repairs .

Did you complete the repair?

Go to Step 13

-

5

Test the headlamp dimmer switch high
beam signal and ground circuits for an open
or high resistance. Refer to Circuit
Testing and Wiring Repairs .
Did you find and correct a condition?

Go to Step 13

Go to Step 6

6

1. Place the headlamp switch in the ON

position.

2. Connect a fused jumper from ground

to the headlamp high beam dimmer
switch signal terminal of the turn
signal/multifunction switch connector.

Do the high beam headlamps illuminate?

Go to Step 8

Go to Step 7

7

Connect a fused jumper from B+ voltage to
the beam select relay control circuit
terminal at the beam select relay in the
underhood fuse block.
Do the high beam headlamps illuminate?

Go to Step 9

Go to Step 11

8

Inspect for poor connections at the harness
connector of the turn signal/multifunction
switch. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 13

Go to Step 12

9

Inspect for poor connections at the harness
connector of the body control module
(BCM). Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 13

Go to Step 10

10

Replace the BCM. Refer to Control
Module References for replacement, setup
and programming.
Did you complete the replacement?

Go to Step 13

-

11

Replace the beam select relay. Refer to
Relay Replacement (Attached to Wire
Harness) or Relay Replacement (Within

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

HEADLAMPS INOPERATIVE - LOW BEAMS

Headlamps Inoperative - Low Beams

an Electrical Center) .
Did you complete the repair?

Go to Step 13

-

12

Replace the turn signal/multifunction
switch. Refer to Turn Signal
Multifunction Switch Replacement .
Did you complete the repair?

Go to Step 13

-

13

1. Use the scan tool in order to clear any

induced DTCs.

2. 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: Headlights/Daytime Running Lights (DRL) Schematics
Connector End View Reference: Lighting Systems Connector End Views, Data
Communication Connector End Views or Wiper/Washer Connector End Views

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to Step 2

Go to
Diagnostic
System Check -
Vehicle

2

Verify that the low beam headlamps are
inoperative.
Do the low beam headlamps operate
normally?

Go to Testing
for Intermittent
Conditions and
Poor
Connections

Go to Step 3

3

Is only one low beam headlamp
inoperative?

Go to Step 4

Go to Step 5

1. Inspect the inoperative bulb for an

open filament and connector for poor
terminal contact and replace/repair,
as necessary. Refer to Headlamp
Bulb Replacement or Wiring
Repairs .

2. If the condition above does not exist,

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3