Hummer H3. Manual — part 1737

system and where the procedure is located.

SCAN TOOL OUTPUT CONTROLS

Scan Tool Output Controls

SCAN TOOL DATA LIST

Scan Tool Data List

SCAN TOOL DATA DEFINITIONS

Use the scan tool data display values and definitions information in order to assist in diagnosing
vehicle malfunctions. Compare the vehicles actual scan tool data display with the typical data
value in the table. Use the data in order to aid in understanding the nature of the concern when the
vehicle data display does not match the typical data values. Refer to Scan Tool Data List.

The typical scan tool data values were taken from a known good vehicle under the following
conditions:

The ignition switch is in the ON position.

The windshield wiper/washer switch is OFF.

Washer Switch

The body control module (BCM) uses this input to determine if the wash switch is pressed.
If it is pressed, the BCM commands the wiper micro relay ON and keeps it ON until 2 wipe
cycles have completed after the switch has been released.

Scan Tool

Output Control

Additional Menu

Selection

Description

Wiper Relay

Miscellaneous Test

This output control commands the wiper micro
relay ON and OFF. The wiper motor will operate at
low speed when the wiper micro relay is ON.

Scan Tool Parameter

Data List

Units Displayed

Typical Data

Value

Ignition On/Engine Off

Washer Switch

Inputs

On/Off

Off

Wiper Delay Input

Data

volts

0

Wiper Park Switch

Inputs

Active/Inactive

Active

Wiper Relay Cmd.

Outputs

On/Off

Off

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3

Wiper Delay Input

The BCM uses this input to determine if it should command the wiper micro relay ON and
the length of the delay between wipes. The scan tool displays 0 volts when the windshield
wiper switch is OFF.

Wiper Park Switch

The BCM uses this input to determine if the wipers are approaching the park position. The
scan tool displays Active when the BCM detects ground on the windshield wiper motor
park switch signal circuit.

Wiper Relay Cmd.

This output displays whether or not the BCM or any other voltage source, is providing
voltage for the wiper micro relay. ON is displayed when the BCM detects voltage on the
windshield wiper switch signal 2 circuit.

DTC B3715, B3716, B3717, B3718 OR B3719

Circuit Description

The body control module (BCM) controls and monitors the state of the ON/OFF wiper relay
control circuit. When the windshield wiper switch is placed in to a low speed setting, a signal is
applied to the BCM. The BCM then applies battery positive voltage to the coil side of the
ON/OFF WPR relay through the relay control circuit. This energizes the relay, allowing battery
positive voltage from the FRT/WPR fuse through the switched side of the ON/OFF WPR relay
through the HI/LOW WPR relay and to the windshield wiper motor. Ground is applied at all
times to the coil sides of the wiper relays and the windshield wiper motor from G105.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

DTC B3717 Front Wiper Relay Drive Circuit Low

DTC B3718 Front Wiper Relay Drive Circuit High

Conditions for Running the DTCs

The ignition is ON.

The ignition voltage is between 9-18.5 volts.

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3

Conditions for Setting the DTCs

The following conditions will cause these DTCs to set:

DTC B3717, the BCM detects a low voltage level on the supply circuit of the wiper micro
relay for 1 second when the relay is energized.

DTC B3718, the BCM detects a high voltage level on the supply circuit of the wiper micro
relay for 1 second when the relay is de-energized.

Action Taken When the DTC Sets

The BCM de-energizes the wiper micro relay, until the wiper switch is turned OFF and ON.

Conditions for Clearing the DTCs

DTC B3717 will change from current to history when the windshield wiper switch is turned
OFF and ON and the condition is no longer present.

DTC B3718 will change from current to history when the condition is no longer present.

A history DTC will clear after 100 ignition cycles, without a repeat of the malfunction.

DTC B3715, B3716, B3717, B3718 or B3719

Step

Action

Yes

No

Schematic Reference: Wiper/Washer Schematics
Connector End View Reference: 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

1. Turn the ignition to the ON position.

2. Turn the wiper switch to the low

position.

Do the windshield wipers operate?

Go to Testing
for Intermittent
Conditions and
Poor
Connections

Go to Step 3

3

1. Turn the ignition to the OFF

position.

2. Turn the wiper switch OFF.

3. Remove the ON/OFF WPR relay

from the underhood fuse block.

4. Using a test lamp connected to

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3

ground, probe the relay control
circuit at the underhood fuse block.

Does the test lamp illuminate?

Go to Step 8

Go to Step 4

4

1. Leave the test lamp connected.

2. Turn the ignition to the ON position.

3. Turn the wiper switch to the low

position.

Does the test lamp illuminate?

Go to Step 5

Go to Step 6

5

1. Turn the wiper switch to the OFF

position.

2. Turn the ignition to the OFF

position.

3. Using a test lamp, probe the relay

control circuit and the ground circuit
of the relay at the underhood fuse
block.

4. Turn the ignition to the ON position.

5. Turn the wiper switch to the low

position.

Does the test lamp illuminate?

Go to Step 9

Go to Step 7

6

Test for a poor connection, an open or
short to ground in the ON/OFF wiper
relay control circuit. Refer to Circuit
Testing and Wiring Repairs .
Did you find and correct the condition?

Go to Step 12

Go to Step 10

7

Test for a poor connection or an open in
the ground circuit of the ON/OFF WPR
relay. Refer to Circuit Testing and
Wiring Repairs .
Did you find and correct the condition?

Go to Step 12

Go to Step 11

8

Repair a short to battery positive voltage
in the ON/OFF wiper relay control
circuit. Refer to Circuit Testing and
Wiring Repairs .

2007 Hummer H3

2007 ACCESSORIES & EQUIPMENT Wipers and Washers - H3