Chevrolet Silverado / GMC Sierra. Service manual — part 2296

Fig. 5: Horn - Right Side (Chevrolet)
Courtesy of GENERAL MOTORS CORP.

STEERING WHEEL HORN SWITCH REPLACEMENT

Callout

Component Name

Preliminary Procedure:
Remove the headlamp. Refer to Headlamp Replacement (GMC HD) or Headlamp
Replacement (Chevrolet) .

1

Right Side Horn Bolt

Tighten: 9 N.m (80 lb in)

NOTE:

Refer to Fastener Notice .

2

Right Side Horn
Tip: Disconnect the electrical connector.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Horns - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

Fig. 6: Steering Wheel Horn Switch
Courtesy of GENERAL MOTORS CORP.

Callout

Component Name

Preliminary Procedure: Remove the inflatable restraint steering wheel module. Refer to
Inflatable Restraint Steering Wheel Module Replacement .

CAUTION:

Refer to SIR Caution .

1

Horn Switch Bolt (Qty: 4)

NOTE:

Refer to Fastener Notice .

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Horns - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

DESCRIPTION AND OPERATION

HORNS SYSTEM DESCRIPTION AND OPERATION

System Description

The horn system consists of the following components:

HORN fuse

Horn PCB relay

Horn switch

Horn

Body control module (BCM)

System Operation

The vehicle horns are activated whenever the horn switch is depressed.

The BCM commands the horns ON under any of the following conditions:

When the panic button is depressed on the remote control door lock transmitter. For
further information refer to Keyless Entry System Description and Operation .

When the keyless entry system is used to lock the vehicle, a horn chirp may sound to
notify the driver that the vehicle has been locked. The notification feature may be
enabled or disabled through personalization. For further information refer to Keyless
Entry System Description and Operation .

When the OnStar® system is used to sound the horns if equipped. For further
information, refer to OnStar Description and Operation .

Circuit Operation

Battery positive voltage is applied at all times to the horn relay coil and the horn relay switch.
Pressing the horn switch applies ground to the horn relay control circuit. When the horn relay
control circuit is grounded, the horn relay is energized and battery positive voltage is applied to
the horn through the horn control circuit. The horn will sound as long as ground is applied to the
horn relay control circuit.

Tighten: 8 N.m (71 lb in)

2

Horn Switch
Procedure:
Disconnect any electrical connectors as needed.

2008 Chevrolet Silverado 1500

2008 ACCESSORIES & EQUIPMENT Horns - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra & Silverado

2008 HVAC

Heating, Ventilation, and Air Conditioning - Cab & Chassis Sierra, Cab & Chassis Silverado,

Sierra & Silverado

SPECIFICATIONS

FASTENER TIGHTENING SPECIFICATIONS

Application

Specification

Metric

English

A/C High Pressure Recirculation Switch

6 N.m

53 lb in

A/C Low Pressure Switch

6 N.m

53 lb in

A/C Refrigerant Filter Retaining Nuts

15 N.m

11 lb ft

Accumulator Bracket Nut

9 N.m

80 lb in

Accumulator Clamp Bolt

10 N.m

8 lb ft

Air Distribution Duct Screws

1.6 N.m

14 lb in

Air Outlet Mounting Screw

1.6 N.m

14 lb in

Auxiliary A/C Tubes at the Auxiliary HVAC
Module

16 N.m

12 lb ft

Auxiliary Evaporator Tube to TXV Nut

28 N.m

21 lb ft

Auxiliary HVAC Module A/C Line Nut

16 N.m

12 lb ft

Auxiliary HVAC Module Mounting Nuts to Vehicle

9 N.m

80 lb in

Blower Motor Insulating Cover Screw

1.6 N.m

14 lb in

Blower Motor Relay/Resistor Screw

1.6 N.m

14 lb in

Compressor Bracket Mounting Bolts

50 N.m

37 lb ft

Compressor Clutch Coil Connector Retaining
Bracket Screw

9 N.m

80 lb in

Compressor Clutch Plate Retaining Bolt

18 N.m

13 lb ft

Compressor Discharge Hose Nut at Compressor

16 N.m

12 lb ft

Compressor Hose Bolt to Compressor (L18
Harrison)

34 N.m

25 lb ft

Compressor Mounting Bolts (L18 Harrison)

50 N.m

37 lb ft

Compressor Mounting Bolts (LR4, LM7, LQ4
Denso)

50 N.m

37 lb ft

Compressor Suction/Discharge Hose Bolt

34 N.m

25 lb ft

Compressor Suction Hose Nut to Accumulator

16 N.m

12 lb ft

2008 Chevrolet Silverado 1500

2008 HVAC Heating, Ventilation, and Air Conditioning - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado

2008 Chevrolet Silverado 1500

2008 HVAC Heating, Ventilation, and Air Conditioning - Cab & Chassis Sierra, Cab & Chassis Silverado, Sierra &

Silverado