Hummer H3. Manual — part 1399

DTC B0525 Left Turn Signal Circuit

Conditions for Running the DTC

The battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

When the BCM receives a left turn signal command and the left turn signal indicator supply
voltage circuit is open, shorted to ground or shorted to voltage

Action Taken When the DTC Sets

The left turn signal indicator in the IPC will not operate or will remain always ON.

Conditions for Clearing the MIL/DTC

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

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

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

Test Description

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

4: This step tests if battery positive voltage is constantly being applied to the supply voltage
circuit.

5: This step tests if a condition exists in the supply voltage circuit.

6: This step tests if a condition exists in the ground circuit.

10: After replacement of the IPC, you must calibrate the new cluster for proper operation.

11: After replacement of the BCM, you must calibrate the new module for proper
operation.

DTC B0525 (W/O RPO CW9 )

Step

Action

Yes

No

Schematic Reference: Fog Lights Schematics
Connector End View Reference: Lighting Systems Connector End Views, Displays
and Gages Connector End Views or Data Communication Connector End Views

1

Did you perform the Diagnostic System
Check - Vehicle?

Go to
Diagnostic

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

Go to Step 2

System Check -
Vehicle

2

1. Turn ON the ignition, with the engine

OFF.

2. Activate the turn signals.

Do the exterior turn signals operate
correctly?

Go to Step 3

Go to
Symptoms -
Lighting
Systems

3

1. Turn OFF the ignition.

2. Remove the instrument panel cluster

(IPC). Refer to Instrument Cluster
Replacement (Left Hand Drive) or
Instrument Cluster Replacement
(Right Hand Drive) .

3. Turn ON the ignition, with the engine

OFF.

4. Connect a test lamp between the

ground circuit and the left turn signal
indicator supply voltage circuit at the
IPC connector.

5. Activate the inoperative turn signal

ON and OFF.

Does the test lamp illuminate?

Go to Step 4

Go to Step 5

4

Does the test lamp remain illuminated with
each command?

Go to Step 7

Go to Step 8

5

Test for a short to ground, open or high
resistance in the left turn signal indicator
supply voltage circuit. Refer to Circuit
Testing and Wiring Repairs .
Did you find and correct the condition?

Go to Step 12

Go to Step 6

6

Test for an open or high resistance in the
ground circuit. Refer to Circuit Testing
and Wiring Repairs .
Did you find and correct the condition?

Go to Step 12

Go to Step 9

7

Test the left turn signal indicator supply
voltage circuit for a short to voltage. Refer

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

DTC B0525 (WITH RPO CW9)

Circuit Description

When the body control module (BCM) senses that the rear fog lamp switch signal circuit is
grounded momentarily by pressing the rear fog lamp switch, the BCM energizes the rear fog lamp
relay by grounding the rear fog lamp relay control circuit. The rear fog lamp indicator is also
illuminated.

DTC Descriptor

This diagnostic procedure supports the following DTC:

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

Go to Step 12

Go to Step 9

8

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

Go to Step 12

Go to Step 10

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 12

Go to Step 11

10

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

Go to Step 12

-

11

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

Go to Step 12

-

12

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

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3

DTC B0525 Rear Fog Lamp Relay Fault

Conditions for Running the DTC

The battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

When the BCM receives a rear fog lamp switch OFF command and the rear fog lamp relay
control circuit is shorted to ground

When the BCM receives a rear fog lamp switch ON command and the rear fog lamp relay
control circuit is shorted to voltage or open

Action Taken When the DTC Sets

The rear fog lamps will not operate or will remain always ON.

Conditions for Clearing the MIL/DTC

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

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

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

Test Description

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

2: Listen for an audible click when the rear fog lamp relay operates. Command both the ON
and OFF states. Repeat the commands as necessary.

3: This step tests for ground at the coil side of the rear fog lamp relay.

4: This step verifies that the BCM is providing battery positive voltage to the rear fog lamp
relay.

5: This step tests if battery positive voltage is constantly being applied to the rear fog lamp
relay.

6: This step tests if a condition exists in the rear fog lamp relay control circuit.

12: After replacement of the BCM, you must calibrate the new module for proper
operation.

DTC B0525 (With RPO CW9)

Step

Action

Yes

No

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Lighting - H3