GM Service Manual Online
For 1990-2009 cars only

Name

Location

Locator View

Connector End View

Ambient Light Sensor

On the top center of the instrument panel (IP) in the grille assembly

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Automatic Transfer Case (ATC) Select Switch

To the left of the instrument cluster above the headlamp switch on the IP

Transfer Case Control Component Views in Automatic Transfer Case

Transfer Case Control Connector End Views in Automatic Transfer Case

Body Control Module (BCM)

On the lower left side of the IP below the steering column

Body Control System Component Views

Body Control System Connector End Views

Cargo Lamp Switch

To the right side of the steering column in the IP

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Center High Mounted Stop/Cargo Lamp (Pickup)

On the center top rear of the cab

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Courtesy Lamp Relay

In the mid bussed electrical center (MBEC)

Electrical Center Identification Views in Wiring Systems

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Cruise Control Module

On the left front of the dash in the engine compartment

Cruise Control Component Views in Cruise Control

Cruise Control Connector End Views in Cruise Control

Data Link Connector (DLC)

On the left lower dash below the steering column

Data Link Communications Component Views in Wiring Systems

Data Link Communications Connector End Views in Wiring Systems

Daytime Running Lamps (DRL) Relay

In the UBEC

Electrical Center Identification Views in Wiring Systems

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Door Lock Relay

In the left bussed electrical center (LBEC)

Electrical Center Identification Views in Wiring Systems

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Door Unlock Relay

In the LBEC

Electrical Center Identification Views in Wiring Systems

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Fog Lamp Relay

In the UBEC

Electrical Center Identification Views in Wiring Systems

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Fog Lamp Switch

To the right of the steering column on the IP

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Fog Lamp, LH

On the left side of the front bumper

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Fog Lamp, RH

On the right side of the front bumper

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Headlamp Panel Dimmer Switch

To the left of the steering wheel on the IP

Lighting Systems Component Views in Lighting Systems

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Headlamp Relay

In the UBEC

Electrical Center Identification Views in Wiring Systems

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Headlamp Dimmer Switch

Inside the steering column, controlled by the multifunction switch

Lighting Systems Component Views in Lighting Systems

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Lighting Systems Connector End Views in Lighting Systems

High Beam Lamp, LH

On the left front of the vehicle

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

High Beam Lamp, RH

On the right front of the vehicle

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Horn (High), RH

On the right lower corner of the radiator core support

Horn Component Views in Horns

Horn Connector End Views in Horns

Horn Relay

In the UBEC

Electrical Center Identification Views in Wiring Systems

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Horn Switch

At the top of the steering column on the steering wheel

Electrical Center Identification Views in Wiring Systems

Horn Connector End Views in Horns

Ignition Switch

Near the lower part of the steering column behind the instrument cluster

--

Power and Grounding Connector End Views in Wiring Systems

Inadvertant Power Relay

In the MBEC

Electrical Center Identification Views in Wiring Systems

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Key In Ignition Switch

Part of the ignition cylinder

--

--

Left Bussed Electrical Center (LBEC)

On the lower left side of the IP

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Low Beam Lamp, LH

At the left front of the vehicle

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Low Beam Lamp, RH

At the right front of the vehicle

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Mid Bussed Electrical Center (MBEC)

Under the left side of the instrument panel near the left kick panel

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Mini Wedge (Door Jamb Switch), LH

Part of the left door latch assembly

Power Door Systems Component Views in Doors

Lighting Systems Connector End Views in Lighting Systems

Mini Wedge (Door Jamb Switch), RH

Part of the right door latch assembly

Power Door Systems Component Views in Doors

Lighting Systems Connector End Views in Lighting Systems

Park Brake Switch

Part of the park brake assembly

Hydraulic Brake Component Views in Hydraulic Brakes

Hydraulic Brake Connector End Views in Hydraulic Brakes

Park Lamp Relay

In the MBEC

Electrical Center Identification Views in Wiring Systems

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Passlock Sensor

Part of the ignition cylinder

--

--

Power Door Lock Switch, LH

On the left door tirm panel armrest

Power Door Systems Component Views in Doors

Power Door Systems Connector End Views in Doors

Power Door Lock Switch, RH

On the right door trim panel armrest

Power Door Systems Component Views in Doors

Power Door Systems Connector End Views in Doors

Power Window/Door Lock Switch, LH

On the left door trim panel armrest

Power Door Systems Component Views in Doors

Power Door Systems Connector End Views in Doors

Power Window/Door Lock Switch, RH

On the right door trim panel armrest

Power Door Systems Component Views in Doors

Power Door Systems Connector End Views in Doors

Powertrain Control Module (PCM)

Near the left front inside the engine compartment

Engine Controls Component Views in Engine Controls - 4.8L, 5.3L, 6.0L

Engine Controls Connector End Views in Engine Controls - 4.8L, 5.3L, 6.0L

Radio

In the center of the IP

Entertainment Component Views in Entertainment

Entertainment Connector End Views in Entertainment

Remote Control Door Lock Receiver

In the top center of the IP near the instrument cluster

Keyless Entry Component Views in Keyless Entry

Keyless Entry Connector End Views in Keyless Entry

Retained Accessory Power (RAP) Relay

In the LBEC

Electrical Center Identification Views in Wiring Systems

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Right Bussed Electrical Center (RBEC)

On the lower right side of the IP

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

Roof Beacon Switch

At the center of the IP

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Roof Marker Lamps

On top of the roof

Lighting Systems Component Views in Lighting Systems

Lighting Systems Connector End Views in Lighting Systems

Seat Belt Switch

In the seat belt buckle

--

Instrument Panel, Gages, and Console Connector End Views in Instrument Panel, Gauges and Console

Tow/Haul Switch

In the end of the automatic transmission shift lever

--

Automatic Transmission Inline Harness Connector End View in Automatic Transmission - 4L60E

Automatic Transmission Inline Harness Connector End View in Automatic Transmission - 4L80E

Turn/Hazard Switch

Inside the steering column multi function switch

--

Lighting Systems Connector End Views in Lighting Systems

Underhood Bussed Electrical Center (UBEC)

At the left side of the engine compartment near the battery

Power and Grounding Component Views in Wiring Systems

Power and Grounding Connector End Views in Wiring Systems

C125

At the left front of the engine compartment on the radiator support (Snowplow Package)

--

Inline Harness Connector End Views in Wiring Systems

C127

At the right front of the engine compartment on the radiator support (Snowplow Package)

--

Inline Harness Connector End Views in Wiring Systems

C200

At the left kick panel next to the A pillar

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C201

On the steering column under the IP

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C201B

On the steering column under the IP

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C201C

On the steering column under the IP

Harness Routing Views in Wiring Systems

Inline Harness Connector End Views in Wiring Systems

C297

On the lower right side of the IP

--

Inline Harness Connector End Views in Wiring Systems

C299

At the right side of the IP at the kick panel

--

Inline Harness Connector End Views in Wiring Systems

C303

Under the right seat

--

Inline Harness Connector End Views in Wiring Systems

C305

Under the left front seat

--

Inline Harness Connector End Views in Wiring Systems

G100

On the left radiator support bracket

Power and Grounding Component Views in Wiring Systems

--

G102

On the right front of the engine block (4.3L)

--

--

G102

On the left front of the engine block (4.8L, 5.3L, 6.0L)

Power and Grounding Component Views in Wiring Systems

--

G200

On the right upper IP at the A pillar

Power and Grounding Component Views in Wiring Systems

--

G203

On the left upper IP at the A pillar

Power and Grounding Component Views in Wiring Systems

--

G304

Under the driver seat

Power and Grounding Component Views in Wiring Systems

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P100

At the left rear of the engine compartment in the front of the dash

Power and Grounding Component Views in Wiring Systems

--

P500

Between the left front door and the body

Power and Grounding Component Views in Wiring Systems

--

P600

Between the right front door and the body

Power and Grounding Component Views in Wiring Systems

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S100

In the forward lamp harness

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--

S101

In the forward lamp harness

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--

S102

In the engine harness

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