Contents Wiring diagrams Section: Ignition Switch/steering Lock All sections

Steering Wheel and Steering Column: Overview GMC Sierra 1500

Ignition Switch/steering Lock 4 illustrations ~376 words

Steering Wheel and Column Schematic Icons

Steering Wheel and Column Schematic Icons Icon Icon Definition CAUTION: When performing service on or near the SIR components or the SIR wiring, the SIR system must be disabled. Refer to SIR Disabling and Enabling Zones. Failure to observe the correct procedure could cause deployment of the SIR components, personal injury, or unnecessary SIR system repairs

Scheme 1

Scheme 1: Steering Wheel Schematics

Scheme 2

Scheme 2: Steering Column Disassembled View (Column Shift Lean Shaft)
CalloutComponent Name
1Upper Trim Cover
2Lower Trim Cover
3Shift Lever Seal
4Shift Lever Screw
5Shift Lever
6Flanged Prevailing Torque Nut
7Retaining Ring
8SIR Coil
9SIR Coil and Harness Assembly
10Wave Washer
11Bearing Retainer
12Cam Orientation Plate
13Turn Signal Cancel Cam Assembly
14Upper Bearing Spring
15Upper Bearing Inner Race Seat
16Inner Race
17Turn Signal Switch Housing
18TORX® Head Screw
19Pan Head Tapping Screws
20Ignition Lock Cylinder Case Assembly
21Pan Head Tapping Screw
22Ignition Switch Assembly
23Pan Head Tapping Screws
24Turn Signal and Multifunction Switch Assembly
25Axial Position Assurance Connector
26Steering Column Tilt Head Assembly
27Spring Guide
28Tilt Spring
29Release Lever Pin
30Bearing Assembly
31Steering Column Shaft Assembly
32Tilt Knob
33Pan Head Tapping Screws
34Oval Head Soc Tap Screws
35Linear Shift Assembly
36TORX® Head Screws
37Pivot Pins
38Steering Column Support Assembly
39Steering Column Jacket Assembly
40Automatic Transmission Shift Lock Control
41Adapter and Bearing Assembly
42Steering Wheel Position Sensor Assembly
43Sensor Retainer
44Hexagon Head Nut
45Intermediate Shaft
46Bolt and Retainer Assembly

Callouts For (Scheme 2)

Scheme 3

Scheme 3: Steering Column Disassembled View (Floor Shift Lean Shaft)
CalloutComponent Name
1Upper Trim Cover
2Lower Trim Cover
3Flanged Prevailing Torque Nut
4Retaining Ring
5SIR Coil
6SIR Coil and Harness Assembly
7Wave Washer
8Bearing Retainer
9Shaft Lock Shield Assembly
10Turn Signal Cancel Cam Assembly
11Upper Bearing Spring
12Upper Bearing Inner Race Seat
13Inner Race
14Lock Bolt
15Lock Bolt Spring
16Pan Head Tapping Screws
17TORX® Head Screw
18Ignition Lock Cylinder Case Assembly
19Pan Head Tapping Screw
20Ignition Switch Assembly
21Steering Column Tilt Head Assembly
22TORX® Head Screw
23Release Lever Pin
24Spring Guide
25Tilt Spring
26Bearing Assembly
27Pan Head Tapping Screws
28Turn Signal and Multifunction Switch Assembly
29Axial Position Assurance Connector
30Tilt Knob
31Pan Head Tapping Screws
32Steering Column Shaft Assembly
33TORX® Head Screws
34Pivot Pins
35Steering Column Support Assembly
36Steering Column Jacket Assembly
37Adapter and Bearing Assembly
38Bolt and Retainer Assembly
39Hexagon Head Nut
40Intermediate Shaft Assembly

Callouts For (Scheme 3)

Scheme 4

Scheme 4: Steering Wheel and Column Component Views
CalloutComponent Name
1C277 Steering Column Harness to Steering Wheel Harness
2Inflatable Restraint Steering Wheel Coil C2 (AOL)
3Inflatable Restraint Steering Wheel Coil C1
4Inflatable Restraint Steering Wheel Coil
5C201 Steering Wheel Harness to I/P Harness
6C221 Steering Wheel Harness to I/P Harness
7C277 Steering Wheel Harness to steering Column Harness
8Steering Wheel Control Switch Assembly-Upper Right (UK3)
9Steering Wheel Control Switch Assembly-Lower Right (UK3)
10Steering Wheel Control Switch Assembly-Lower Left (UK3)
11Steering Wheel Control Switch Assembly-Upper Left (UK3)

Callouts For (Scheme 4)

Circuit/System Description

The body control module (BCM) supplies 12 volts to the audio steering wheel control multiple momentary contact switches and monitors the return signal. Each switch is associated to a set resistance value, when pressed a specific voltage drop occurs through a series of resistors unique to that switch. The BCM identifies the selection, then sends a serial data message that is received by the component controlled, activating the feature.

The body control module (BCM) supplies 12 volts to the audio steering wheel control multiple momentary contact switches and monitors the return signal. Each switch is associated to a set resistance value, when pressed a specific voltage drop occurs through a series of resistors unique to that switch. The BCM identifies the selection, then sends a serial data message that is received by the component controlled, activating the feature.

Steering Wheel Controls Description and Operation

The steering wheel control switches duplicate the function of the primary controls of the associated component, through a network of multiple momentary contact switches and a series of resistors. The body control module (BCM) supplies voltage to the switches and monitors the return signal for when a switch is pressed, a specific voltage drop occurs. The BCM identifies the one selected, then sends a serial data message that is received by the component controlled, activating the feature.

This section is intended to diagnose the circuits between the BCM and the steering wheel control switches. If the primary control for the device is inoperative, refer to the appropriate section for the component the steering wheel control switch is functioning.

Steering Wheel and Column Description and Operation

The steering wheel and column has 4 primary functions

  1. Vehicle steering
  2. Vehicle security
  3. Driver convenience
  4. Driver safety