Safety Warning

DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.

2003 Cadillac CTS AutomaticFACTORY OEM SERVICE PROCEDURE

Component Locations

COMPONENT LOCATIONS

Component

Locations

Engine Control Module (ECM)

In Engine Compartment, In Right Front Corner

STARTER Fuse

In Underhood Fuse Block

Starter Motor ⁽¹⁾

In Engine Compartment, On RR Side Of Engine

STARTER Relay

In Underhood Fuse Block

Starter Solenoid ⁽¹⁾

In Engine Compartment, On RR Side Of Engine, On Top Of Starter

⁽¹⁾	For view of starter components, see Fig 1 .

Fig 1: Locating Starter Components

Courtesy of GENERAL MOTORS CORP.

Chapter Navigation

Return to Chapter: Starting System

Factory Service Tools

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.