Hummer H1 (2006+). Manual - part 352

12-84

Electrical System

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2

Using a DVOM,, check the resistance to ground 
at the black wire (CKT 59) going to the right side 
windshield. Does the resistance to ground meet 
the specified range?

<.2

1

Go to step 3.

Repair the open 

or bad connection 

in CKT 59 

between the 

windshield and 

G4.

3

Remove the right hand heated windshield relay from 
the exterior fuse box. Check the voltage drop 
between the brown wire (CKT 580) and the black 
wire (CKT 59). With the ignition in the “RUN” 
position, turn the heated windshield switch to “ON”. 
Is the specified voltage present?

+12v

Go to step 4.

Repair the open 

or bad connection 

in CKT 580 
between the 

heated wind-

shield switch and 

the heated wind-

shield relay (R-2).

4

With the ignition still in the “RUN” position. Preform 
a voltage drop test between the black wire (CKT 59) 
and the purple wire (CKT 739). Is the specified volt-
age present?

+12v

Go to step 5.

Repair the open 

or bad connection 

in CKT 739 

between fuse 2C 

and R-2.

5

With a DVOM,, check the resistance between the 
purple wire (CKT 739) at the relay and the purple 
wire (CKT 739) at the windshield. Does the resis-
tance meet the specified value?

<.2

1

Replace relay 

R-2.

Repair the open 

or bad connection 

in CKT 739 

between the left 

side heated wind-

shield and R-2.

 Both Heated Windshields Inoperative  (Figure 12-157)

Step

Action

Value(s)

Yes

No

1

Gain access to the heated windshield connections. 
Using a DVOM,, check the resistance to ground 
on the black wires at both windshields. Does the 
resistance meet the specified value?

<.2

1

Go to step 2.

Repair the open 

or bad connection 

in CKT 59 

between the 

windshields and 

G4.

2

Remove the heated windshield switch from the 
bezel. Turn the ignition switch to the “RUN” 
position and turn the heated windshield switch to 
the “ON” position. Using a DVOM, check the 
voltage drop between the brown wire (CKT 580) 
and the black wire (CKT 58). Is the specified 
voltage present?

+12v

Repair the open 

or bad connection 

in CKT 580 
between the 

heated wind-

shield switch and 

the relays.

Go to step 3.

 Right Heated Windshield Inoperative  (Figure 12-157)

Step

Action

Value(s)

Yes

No

______________________________________________________

 Electrical System  12-85

3

Using a DVOM,, measure the resistance to ground 
on the black wire (CKT 59) at the heated windshield 
switch. Does the resistance meet the specification?

<.2

1

Go to step 4.

Repair the open 

or bad connection 

in CKT 59 

between the 

heated wind-

shield switch and 

G4.

4

With the ignition in the “RUN” position and the 
heated windshield switch in the “ON” position. 
Use a DVOM, to check for voltage at both tan 
wires (CKT 83) at the heated windshield switch. 
Is the specified voltage present?

+12v

Replace the 

heated wind-

shield switch.

Repair the open 

or bad connec-

tion in CKT 83 

between the 

windshield

switch and fuse 

1C interior.

 Both Heated Windshields Inoperative  (Figure 12-157)

Step

Action

Value(s)

Yes

No

12-86

Electrical System

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POWER WINDOW SYSTEM

System Description

The power window system is the same for all models except model 89 which does not have the rear windows. All models with power
windows have the following components: a driver side window motor and switch, driver side controls for all windows including the win-
dow lock out switch (Figure 12-59), a front side window motor and switch, a circuit breaker, the power window relay and an express
down window module. All models except the model 89 have a set of rear window motors and switches. 

Figure 12-59:   Power Window Switches

Window Lock Out Switch

The window lock out switch allows the driver to over ride the passengers window controls (Figure 12-60). When activated the win-
dow lock out switch will open the circuit for the passenger activated window controls, thereby giving the driver complete control
of the window switches.

Figure 12-60:   Power Window Lock Out Switch

Express Down Window Module

This module provides automatic full-open of a front power window from a single actuation of the window switch. Once the power
window down switch has been activated for 300ms, the module enters auto mode and the switch can be released. The window will
continue moving downward until one of the following conditions occurs: 

1.

The power window “DOWN” switch is activated. 

2.

The power window “UP” switch is activated. 

3.

The module senses that the power window motor is stalled. 

4.

The module has been in auto mode for 8 seconds.

DOOR SWITCH

L. REAR

R. FRONT

R. REAR

L. FRONT

SWITCH

LOCKOUT

POWER

WINDOW

LOCK OUT

SWITCH

POWER

WINDOW

LOCK OUT

CONNECTOR

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 Electrical System  12-87

 Drivers Window Inoperative 

Step

Action

Value(s)

Yes

No

1.

Do all the other windows operate as designed?

–––

Go to step 2.

Refer to proper chart.

2.

Remove the drivers window switch and harness from 
the bezel. With a DVOM, check the resistance to 
ground on one black wire (CKT 56) and the other 
black wire (CKT 56) at the switch. Does the resis-
tance on each wire meet the specifications?

<.2

1

Go to step 3.

Repair the open or bad con-
nection in CKT 56 between 

the power window switch and 

G4.

3.

Turn the ignition switch to the”Run” position and 
check the voltage on the red wire (CKT 171). Is the 
specified voltage present?

+12v

Go to step 4.

Repair the open or bad con-

nection on CKT 171 between 

the window switch and relay 

R4.

4.

Connect the window switch to the harness. With the igni-
tion in the “Run” position, back probe the purple wire 
(CKT 222) and the yellow wire (CKT 226) with a 
DVOM, set to measure voltage. Operate the window 
switch and observe the voltage polarity. The voltage 
should switch from +12v to -12v with the operation of the 
switch. Does the polarity switch?

+12v to -12v

Go to step 5.

Replace the drivers door 

power window  switch. 

5.

Gain access to the express down window module. With 
the power window switch in the down position, check 
for voltage at the yellow wire (CKT 226). Is the speci-
fied voltage present?

+12v

Go to step 6.

Repair the open or bad connec-

tion on CKT 226 between the 
express down module and the 

window switch.

6.

With the power window switch in the down position, 
check for voltage at the white wire (CKT 228) of the 
express down module. Is the specified voltage 
present?

+12v

Go to step 7.

Replace the express down 

module.

7.

Gain access to the window motor. Disconnect the har-
ness and with a DVOM, check the wires for polarity 
change when the power window switch is operated. 
Does the polarity change?

+12v to -12v

Replace the 

power window 

motor.

Repair the open or bad con-

nection on CKTs 226 and 227 

between the window switch 

and the window motor.

 Express Down Feature Inoperative  (Figure 12-109)

Step

Action

Value(s)

Yes

No

1

Does the drivers window function correctly other 
than the express down feature?

__

Go to step 2.

Refer to proper chart.

2

Gain access to the express down module. with the 
ignition in the “RUN” position, check the red wire 
(CKT 171) for voltage. Is the specified voltage 
present?

+12v

Replace the 

express down 

module.

Repair the open or bad con-

nection on CKT 171 

between the express down 

module and relay R4.