Hummer H2. Manual — part 315

2

2. Turn ON the ignition, with the engine

OFF.

3. With a scan tool, observe the ambient

light sensor parameter in the Body
Control Module (BCM) data list.

Does the scan tool indicate that the ambient
light sensor parameter is within the specified
range?

1.75-

4.9 V

Go to Testing for

Intermittent

Conditions and Poor

Connections in Wiring

Systems

Go to Step 3

3

1. Turn OFF the ignition.

2. Disconnect the ambient light sensor.

3. Turn ON the ignition, with the engine

OFF.

4. With a scan tool, observe the ambient

light sensor parameter.

Does the scan tool indicate that the ambient
light sensor parameter is greater than the
specified value?

4.9 V

Go to Step 4

Go to Step 5

4

1. Turn OFF the ignition.

2. Connect a 3-amp fused jumper wire

between the ambient light sensor low
reference circuit and the ambient light
sensor signal circuit at the ambient light
sensor harness connector.

3. Turn ON the ignition, with the engine

OFF.

4. With a scan tool, observe the ambient

light sensor parameter.

Does the scan tool indicate that the ambient
light sensor parameter is less than the
specified value?

1.75 V

Go to Step 6

Go to Step 7

5

Test the ambient light sensor signal circuit for
a short to ground. Refer toCircuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 13

Go to Step 10

6

Test the ambient light sensor low reference
circuit 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 9

Test the ambient light sensor signal circuit for

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

DTC B3801

Circuit Description

The body control module (BCM) monitors the courtesy lamp switch signal circuit in order to determine when
the courtesy/dome lamps should be illuminated. When the BCM senses that the courtesy lamp switch signal
circuit is grounded when the switch is activated, the BCM will illuminate the courtesy/dome lamps.

7

a short to voltage, a high resistance, or an
open. Refer to Circuit Testing andWiring
Repairs in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 13

Go to Step 8

8

Test the ambient light sensor low reference
circuit for a short to voltage, a 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 13

Go to Step 10

9

Inspect for poor connections at the harness
connector of the ambient light sensor. 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 13

Go to Step 11

10

Inspect for poor connections at the harness
connector of the BCM. 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 13

Go to Step 12

11

Replace the ambient light sensor. Refer to
Ambient Light Sensor Replacement .
Did you complete the replacement?

-

Go to Step 13

-

12

Replace the 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

1. Use the scan tool in order to clear the

DTCs.

2. Operate the vehicle within the

Conditions for Running the DTC as
specified in the supporting text.

Does the DTC reset?

-

Go to Step 2

System OK

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

Conditions for Running the DTC

z

The BCM instrument panel dimmer switch reference voltage must be between 4.5-5.5 volts.

z

The battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC

z

When the instrument panel dimmer switch signal is greater than 1.0 volt.

z

When the BCM receives a courtesy lamp ON request signal from the courtesy lamp switch.

Action Taken When the DTC Sets

The courtesy/dome lamps will not operate.

Conditions for Clearing the MIL/DTC

z

This DTC will clear on current status after the condition for setting the fault is corrected.

z

A history DTC will clear after 100 consecutive ignition cycles without a fault present.

z

History and current DTCs can be cleared using a scan tool.

Diagnostic Aids

z

Test the courtesy lamp switch for sticking in the ON position.

z

Perform a visual inspection for loose or poor connections at all related components. Refer to Testing for
Intermittent Conditions and Poor Connections in Wiring Systems.

DTC B3801

Step

Action

Yes

No

Schematic Reference: Interior 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

1. Install a scan tool.

2. Turn ON the ignition, with the engine

OFF.

3. With a scan tool, observe the courtesy

lamp switch parameter in the Body
Control Module (BCM) data list.

4. Slowly switch the courtesy lamp switch

ON and OFF several times.

Does the scan tool display as expected?

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

Go to Step 3

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2

DTC B3802

Circuit Description

3

1. Turn OFF the ignition.

2. Disconnect the headlamp lamp switch.

3. Turn ON the ignition, with the engine

OFF.

4. With a scan tool, observe the courtesy

lamp switch data parameter.

Does the scan tool display ACTIVE?

Go to Step 4

Go to Step 6

4

Test the signal circuit of the courtesy lamp
switch 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 9

Go to Step 5

5

Inspect for poor connections at the harness
connector of the Body Control Module (BCM).
Refer to Circuit Testing and Wiring Repairs
in Wiring Systems.
Did you find and correct the condition?

Go to Step 9

Go to Step 7

6

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 9

Go to Step 8

7

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 9

-

8

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

Go to Step 9

-

9

1. Use the scan tool in order to clear the

DTCs.

2. Operate the vehicle within the Conditions

for Running the DTC as specified in the
supporting text.

Does the DTC reset?

Go to Step 2

System OK

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Lighting Systems - Hummer H2