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.

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HOMESERVICE MANUALSCHEVROLET2003TRAILBLAZER 4.2 S, 4WDREPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 1449 (SHIFT INTERLOCK SYSTEM)REPAIR INSTRUCTIONSAUTOMATIC TRANSMISSION SHIFT LOCK ACTUATOR REPLACEMENTINSTALLATION PROCEDURE

2003 Chevrolet TrailBlazer 4.2 S, 4WD

Installation Procedure

2003 Chevrolet TrailBlazer 4.2 S, 4WDSECTION Installation Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

Fig 1: Removing/Installing Shift Lock Actuator

Courtesy of GENERAL MOTORS CORP.

In drive position, depress the shift lock actuator button and realign into the shiftier lever.
Push lever to neutral.

NOTE: Refer to Fastener Notice .

Install the top screw through the lever slot.
Tighten: Tighten the BITSI screw to 1.65 N.m (1.2 lb ft).
Shift lever to low.
Install the screw at the rear of the shiftier assembly.
Tighten: Tighten the BITSI screw to 1.65 N.m (1.2 lb ft).

Fig 2: Disconnecting/Connecting Shift Lock Actuator Electrical Connector

Courtesy of GENERAL MOTORS CORP.

Connect the electrical connector (3).

IMPORTANT: After assembling the shift lock actuator, turn the ignition forward but do not start (auxiliary position) and attempt to pull the lever from park with and without the brake pedal depressed to verify there is no gear access without the brake pedal depressed.

RENDER: 1.0x

NO RELATED

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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.