Hummer H2. Manual — part 431

6

1. Turn OFF the ignition.

2. Disconnect the appropriate mirror.

3. Turn ON the ignition, with the engine

OFF.

4. Measure the voltage between the 5 volt

reference circuit at the mirror harness
connector and a good ground.

Does the voltage measure within the specified
range?

4.75 -

5.25 V

Go to Step 7

Go to Step 10

7

Measure the voltage between the 5 volt
reference circuit and the low reference circuit at
the mirror harness connector.
Does the voltage measure within the specified
range?

4.75 -

5.25 V

Go to Step 12

Go to Step 11

8

Test for a short to voltage on the mirror position
signal circuit. Refer to Circuit Testing and
Wiring Repairs in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 16

Go to Step 13

9

Test the mirror position signal circuit for an
open, high resistance, short to ground or battery.
Refer to Circuit Testing and Wiring Repairs
in Wiring Systems.
Did you find and correct the condition?

-

Go to Step 16

Go to Step 13

10

Test the 5 volt reference circuit for an open,
high resistance, short to ground or battery. Refer
to Circuit Testing and Wiring Repairs in
Wiring Systems.
Did you find and correct the condition?

-

Go to Step 16

Go to Step 13

11

Test the low reference circuit for an open, high
resistance or short to battery. Refer to Circuit
Testing and Wiring Repairs in Wiring
Systems.
Did you find and correct the condition?

-

Go to Step 16

Go to Step 13

12

Inspect for poor connections at the harness
connector of the power mirror. 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 16

Go to Step 14

13

Inspect for poor connections at the harness
connector of the DDM/PDM. Refer to Testing
for Intermittent Conditions and Poor
Connections and Connector Repairs in Wiring
Systems.

-

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Doors - Hummer H2

DTC B1640 OR B1645

Circuit Description

The DDM and PDM supply battery voltage to the mirror heating element supply voltage circuit upon receipt of
a class 2 message from the BCM indicating that the rear defrost system is active. The DDM and PDM also
supply a constant ground for the mirror heating elements.

Conditions for Running the DTC

z

System voltage between 9.0-16.0 volts

z

Ignition switch is in the ON position

Conditions for Setting the DTC

When the DDM and PDM supply battery voltage to the mirror heating element supply voltage circuit and it's
shorted to ground.

Action Taken When the DTC Sets

The DDM and PDM will ignore the class 2 message and stop supplying battery voltage on the shorted circuit.

Conditions for Clearing the DTC

Did you find and correct the condition?

Go to Step 16

Go to Step 15

14

Replace the power mirror. Refer to Mirror
Replacement .
Did you complete the replacement?

-

Go to Step 16

-

15

Replace the appropriate door module. Refer to
Switch Replacement - Door Lock and Side
Window - Driver or Switch Replacement -
Door Lock and Side Window -
Passenger .Did you complete the replacement?

IMPORTANT:

Perform the set up procedure for the
appropriate door module. Refer to Service
Programming System (SPS) in Programming.

-

Go to Step 16

-

16

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 Doors - Hummer H2

When the short circuit is no longer present, the DDM/PDM will clear the current DTC and store the DTC as a
history DTC. The history DTC will clear after 50 fault free ignition cycles or in response to a scan tool
command.

DTC B1640 or B1645

Step

Action

Yes

No

Schematic Reference: Outside Mirror Schematics
Connector End View Reference: Power Door Systems Connector End Views

1

Did you perform the Door System Diagnostic System
Check?

Go to

Step 2

Go to Diagnostic System

Check - Door Systems

2

1. Turn ON the ignition, with the engine OFF.

2. Activate the rear defroster switch.

Does DTC B1640 or B1645 set as current in the DDM or
PDM?

Go to

Step 3

Go to Testing for

Intermittent Conditions and

Poor Connections in Wiring

Systems

3

1. Turn OFF the ignition.

2. Disconnect the appropriate heated mirror.

3. Turn ON the ignition, with the engine OFF.

4. Activate the rear defroster switch.

Does DTC B1640 or B1645 set as current in the DDM or
PDM?

Go to

Step 5

Go to Step 4

4

Inspect for poor connections at the heated mirror. Refer to
Testing for Intermittent Conditions and Poor
Connections and to Connector Repairs in Wiring Systems.
Did you find and correct the condition?

Go to

Step 8

Go to Step 6

5

Inspect for poor connections at the harness connector of the
appropriate door module. Refer to Testing for Intermittent
Conditions and Poor Connections and to Connector
Repairs in Wiring Systems.
Did you find and correct the condition?

Go to

Step 8

Go to Step 7

6

Replace the heated mirror. Refer to Mirror Replacement .
Did you complete the replacement?

Go to

Step 8

-

7

Replace the appropriate door module. Refer to Switch
Replacement - Door Lock and Side Window - Driver or
Switch Replacement - Door Lock and Side Window -
Passenger .
Did you complete the replacement?

Go to

Step 8

-

8

1. Use the scan tool in order to clear the DTCs.

2. Operate the vehicle within the Conditions for Running

the DTC.

Does the DTC reset?

Go to

Step 2

System OK

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Doors - Hummer H2

DTC B1722

Circuit Description

The Driver Door Module (DDM) and Passenger Door Module (PDM) switch the mirror fold motor control
circuits to battery voltage and ground in response to mirror extend or retract command.

Conditions for Running the DTC

z

Battery voltage must be between 9.0-16.0 volts.

z

The ignition switch is in the ON position.

z

A mirror extend or retract function must be active.

Conditions for Setting the DTC

When the DDM or PDM switch the mirror fold motor control circuits to battery voltage and ground and one of
the mirror fold motor control circuits are shorted to ground, shorted to battery or open.

Action Taken When the DTC Sets

The DDM or PDM will stop suppling battery voltage and ground to the mirror fold motor and the folding
mirrors will be inoperative.

Conditions for Clearing the DTC

When the fault is no longer present, the door module changes the current DTC to a history DTC. The door
module will clear the history DTC after 50 fault free ignition cycles, or in response to a scan tool command.

DTC B1722

Step

Action

Value

(s)

Yes

No

Schematic Reference: Outside Mirror Schematics
Connector End View Reference:Power Door Systems Connector End Views

1

Did you perform the Door Systems Diagnostic System
Check?

-

Go to

Step

2

Go to Diagnostic System

Check - Door Systems

2

1. Install a scan tool.

2. Turn ON the ignition, with the engine OFF.

3. Place the mirror select switch in the neutral/fold

position.

4. Place the mirror direction switch in both the

left/extend and right/retract positions.

Does DTC B1722 set as a current DTC?

-

Go to

Step

3

Go to Testing for

Intermittent Conditions

and Poor Connections in

Wiring Systems

2004 Hummer H2

2004 ACCESSORIES & EQUIPMENT Doors - Hummer H2