Hummer H1 (2002+). Manual - part 180

 

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 Body  10-91

 

 

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05745159

 

GLASS AND BODY FOR SLANT BACK

Rear Window

 

Removal

 

Remove the twenty two window retaining screws, the window
retainer bracket and the window  (Figure 10-181).

 

Figure 10-181: Slant Door Window Replacement

 

Installation

 

Install the slant door window and the window retainer bracket.
Secure the window to the bracket with the twenty two retaining
screws  (Figure 10-181).

 

Slant Back Side Windows

 

Removal

 

Remove the thirteen window retaining screws, the window re-
taining bracket and the slant back side window
(Figure 10-182).

 

 

 

Figure 10-182: Slant Back Side Window Replacement

 

Installation

 

Install the slant back side window and the window retaining
bracket. Secure the window to the bracket with the thirteen
window retaining screws  (Figure 10-182).

SLANT BACK

WINDOW

SLANT BACK

DOOR

WINDOW RETAINING

SCREW

WINDOW
RETAINER

BRACKET

  

SLANT BACK

SIDE WINDOW

WINDOW 

RETAINING

BRACKET

SIDE WINDOW

RETAINING SCREW

SLANT BACK

 

4-1-00

 

10-92

Body

 

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THIS PAGE INTENTIONALLY BLANK.

 

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 11-1

 

 

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05745159

 

Section 11    Heating/Ventilation/Air Conditioning (HVAC)

 

TABLE OF CONTENTS

 

A/C System Refrigerant and Capacity . . . . . . . . . . . . . . . . . . . .11-5
Air Conditioning/Heater Duct Replacement  . . . . . . . . . . . . . .11-25
Ambient Temperature Switch . . . . . . . . . . . . . . . . . . . . . . . . . .11-34
Auxiliary HVAC Unit

A/C Drain Tube(s) Replacement   . . . . . . . . . . . . . . . . . . .11-48
Blower Motor Replacement  . . . . . . . . . . . . . . . . . . . . . . .11-49
Blower Switch Replacement  . . . . . . . . . . . . . . . . . . . . . .11-47
Evaporator/Heater Core Replacement   . . . . . . . . . . . . . .11-49
Expansion Valve Replacement  . . . . . . . . . . . . . . . . . . . .11-50
Heater Hose Replacement  . . . . . . . . . . . . . . . . . . . . . . . .11-47
High-Pressure Hose Replacement   . . . . . . . . . . . . . . . . .11-48
Low-Pressure Hose Replacement . . . . . . . . . . . . . . . . . .11-49
Replacement  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-46

Blend Door Motor  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-42
Blower Motor Resistor Replacement . . . . . . . . . . . . . . . . . . . .11-35
Climate Control System

A/C Pressure Hose Replacement   . . . . . . . . . . . . . . . . . .11-18
Condenser Replacement  . . . . . . . . . . . . . . . . . . . . . . . . .11-20
Control Head Replacement  . . . . . . . . . . . . . . . . . . . . . . .11-16
Heater Hose Replacement  . . . . . . . . . . . . . . . . . . . . . . . .11-22
Heater/A/C Diagnosis  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-2
System Performance Checks   . . . . . . . . . . . . . . . . . . . . . .11-2

Compressor

Clutch Core Replacement   . . . . . . . . . . . . . . . . . . . . . . . .11-32
Clutch Rotor and/or Bearing Replacement   . . . . . . . . . .11-30
Description   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-1
Replacement  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-28
Shaft Seal Replacement  . . . . . . . . . . . . . . . . . . . . . . . . . .11-32

Condenser  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-34
Controls  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-36
Defrost Duct and Windshield Nozzles Replacement . . . . . . .11-26
Drain Tube Replacement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11-24

Essential Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-51
Evaporator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-43

Air Intake Assembly Replacement  . . . . . . . . . . . . . . . . . 11-45
Cycling Switch Replacement   . . . . . . . . . . . . . . . . . . . . . 11-45

Heater Hose Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-22
High Pressure Cutoff Switch . . . . . . . . . . . . . . . . . . . . . . . . . . 11-35
Low Pressure Cutoff Switch  . . . . . . . . . . . . . . . . . . . . . . . . . . 11-34
Main HVAC Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-37

Blower Motor   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-38
Diverter Doors   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-37
Evaporator   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-38
Expansion Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-38
Heat Unit Cowl Insulation Replacement . . . . . . . . . . . . . 11-24
Heater Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-38
High Pressure Cutoff Switch . . . . . . . . . . . . . . . . . . . . . . 11-38
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-39
Thermostatic Cycling Switch   . . . . . . . . . . . . . . . . . . . . . 11-38

Pressure Hose Torque Specifications  . . . . . . . . . . . . . . . . . . 11-17
Rear Console Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-46
Receiver Dryer Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . 11-21
Receiver/Dryer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-34
Receiver/Dryer Pressure Switch Replacement  . . . . . . . . . . . 11-21
Special Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-52
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-13
System Description. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-1
System Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-8
System Performance Checks. . . . . . . . . . . . . . . . . . . . . . . . . . . 11-2
Unit Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-37
Vacuum Door Motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-41
Water Control Valve  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-22
Water Control Valve Replacement. . . . . . . . . . . . . . . . . . . . . . 11-23

 

HVAC SYSTEM DESCRIPTION 

 

The heating, ventilating, and air conditioning system consists 
of the main unit (heat and A/C, or heat only), auxiliary unit (if 
equipped), ducting for air, hoses to transport refrigerant, cool-
ant hoses, a water valve, A/C compressor, condenser, receiver 
dryer, expansion valve, safety switches, and vacuum pump. 
Function of the system is controlled by the vehicle operator 
using the control panel on the console

 

Auxiliary Unit

 

A secondary HVAC unit is used on all 4-passenger vehicles as
standard equipment. Two-passenger vehicles can be equipped
with an auxiliary unit as an option. The auxiliary unit includes
a secondary heater core, evaporator, expansion valve, blower
motor and controls. Both the heater and A/C work in parallel

with the main unit, requiring that the main system be in opera-
tion to activate the auxiliary unit. The blower in the auxiliary
unit is operated using a 3-position switch on the console and
provides 2 speeds and an off position.

 

A/C COMPRESSOR DESCRIPTION

 

All 2000 vehicles use a common Harrison model HR6 com-
pressor. The compressor is belt driven off the engine accessory
drive, and utilizes an electric clutch to engage and disengage
the compressor drive. The compressor is lubricated with re-
quired GM PAG oil. The compressor is specifically designed
to operate with R134a refrigerant.

 

11-2

Heating/Ventilation/Air Conditioning (HVAC)

 

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SYSTEM PERFORMANCE CHECKS 

 

Before performing any air conditioning repair, perform the fol-
lowing:

1.

Check drivebelt for wear, damage, or loss of tension. 
Replace drivebelt as necessary.

1.

Check compressor for secure mounting and proper
alignment. Tighten loose hardware and align as necessary.

2.

Visually inspect compressor, hoses and other accessible
parts of system for damage or leaks. Look for patches of
dirt, dust, and oil build-up. Refrigerant leaks usually
involve compressor oil loss. This is especially applicable
to clutch end of compressor.

3.

Verify operation of climate control system by performing
following:

a.

With the mode (air flow) control knob set to OFF, run
engine to operating temperature (180°-240°F (82°-
116°C)).

b.

Rotate temperature control knob clockwise until it
stops at the warmest setting.

c.

Rotate mode control knob counterclockwise until it
stops at the face setting.

d.

Turn fan control knob to any setting above LO and
note direction and temperature of air flow.

e.

Verify that heated air is coming from instrument
panel vents.

f.

Rotate mode control knob clockwise to the next
setting, floor vents, and verify that heated air comes
from appropriate vents.

g.

Continue checking the air flow positions, floor/defrost
blend, and defrost.

 

NOTE: 

 

Any time the air flow control knob is placed in defrost

or a defrost blend position (with an ambient temperature above
40°F), the compressor clutch engages to dehumidify the in-
coming air.

h.

Rotate the temperature control knob counterclockwise
to its coldest extreme. Verify that cold air comes from
the defrost vents. If the outside air temperature is
40°F or warmer, the refrigeration system will be
responsible for cooling the air. If it is cooler than
40°F, the compressor will not cycle and the incoming
air will simply be the outside air directed into the
passenger compartment.

i.

Rotate the mode control knob counterclockwise until
it stops at the Max A/C panel setting and verify that
compressor clutch engages and air becomes colder.
Turn the mode dial to the A/C setting. Verify that the
air recirculation door closes, and the system brings in
outside air.

j.

Check that blower motor delivers air at four different
speeds. If not, perform electrical troubleshooting.
Repair or replace blower motor, switch, relay, or
blower motor resistor block.

k.

Check water control valve operation. Heater Shutoff
Valve should open completely when temperature
control knob is rotated clockwise.

 

Heating System Tests

 

In most cases, a low heat condition means an insufficient quan-
tity of heated engine coolant is flowing through the heater core.
Check as follows:

1.

Check engine coolant level. If level is low, add coolant and 
inspect for leaks. If coolant level is correct, continue with 
tests.

2.

Check pressure cap on surge tank for improper sealing
with tester J–24460-01 or equivalent. If cap is OK,
continue with tests. Replace cap if it fails to seal and
recheck heater operation.

3.

Set heater controls to highest heat setting.

4.

Operate engine until coolant is at normal operating
temperature (180-220° F or 82-113° C).

5.

Check temperature of coolant flowing through heater core
inlet and outlet hoses.

•  If both hoses feel hot and are about the same tempera-

ture, water control valve is OK and core is not restricted. 
Continue with test.

• If both hoses are only warm (or even cool), engine is ei-

ther not at operating temperature, or a water pump or 
thermostat problem has occurred.

• If inlet hose is cool, or only slightly warm, water control 

valve or vacuum solenoid problem has occurred. Test as 
described in this section.

6.

If heat output is still unsatisfactory but all else checks
correctly, problem is with heat door in main unit, or in
outlet ducts.

 

4-1-00