Hummer H3. Manual — part 1410

This DTC will clear immediately after the condition for setting the fault is corrected.

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

Use a scan tool in order to clear history and current DTCs.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

2: This step verifies that the value displayed is within the specified range.

3: This step tests for the proper operation of the circuit in the high voltage range.

4: This step tests for the proper operation of the circuit in the low voltage range. If the fuse
in the jumper opens when you perform this test, the signal circuit is shorted to voltage.

DTC B2647 or B2648

Step

Action

Value(s)

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

1. Install a scan tool.

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 Go to Step 3

1. Turn OFF the ignition.

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

3

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 to Circuit
Testing and Wiring Repairs .
Did you find and correct the
condition?

-

Go to Step 13

Go to Step

10

Test the ambient light sensor
low reference circuit for a short

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

6

to ground. Refer to Circuit
Testing and Wiring Repairs .
Did you find and correct the
condition?

-

Go to Step 13 Go to Step 9

7

Test the ambient light sensor
signal circuit for a short to
voltage, a high resistance or an
open. Refer to Circuit Testing
and Wiring Repairs .
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 .
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 .
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 .
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

-

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

SYMPTOMS - LIGHTING SYSTEMS

1. Perform the Diagnostic System Check - Vehicle before using the Symptom Tables in

order to verify that all of the following are true:

There are no DTCs set.

The control modules can communicate via the serial data link.

2. Review the system operation and circuit descriptions that apply to the customer complaint in

order to familiarize yourself with the system functions. Refer to the following list:

Exterior Lighting Systems Description and Operation

Interior Lighting Systems Description and Operation

Visual/Physical Inspection

Inspect for aftermarket devices which could affect the operation of the lighting system.
Refer to Checking Aftermarket Accessories .

Inspect the easily accessible or visible system components for obvious damage or conditions
which could cause the symptom.

Intermittent

replacement?

Go to Step 13

-

12

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

-

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

IMPORTANT: The following steps must be completed before using the symptom

tables.

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3