NOTE: This procedure allows relearning of BCM or PCM learned data code after replacement of BCM, sensor or PCM. DTC B3031 will set when entering programming mode.

Turn ignition off. Replace failed component. With transmission in Park (A/T) or Neutral (M/T), momentarily turn ignition switch to START position (engine will not start), and then leave in RUN position. SECURITY indicator light will stay on for 10 minutes. After 10 minutes, when light turns off, turn ignition switch to OFF position for 5 seconds.
Repeat step 1 twice more. Auto learn procedure will be completed during next start attempt. If VCM/PCM was replaced, reprogram VCM/PCM. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE.
Using scan tool following scan tool manufacturer's instructions, check for DTCs. If Passlock(tm) DTCs exist, see SELF-DIAGNOSTIC SYSTEM in ANTI-THEFT SYSTEMS - BLAZER, BRAVADA, ENVOY, JIMMY, SONOMA & S10 PICKUP article. If engine performance-related DTCs exist, see appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. After repairs, check system operation. See DIAGNOSTIC SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM in ANTI-THEFT SYSTEMS - BLAZER, BRAVADA, ENVOY, JIMMY, SONOMA & S10 PICKUP article.

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.

Safety Warning

PASSLOCK(tm) AUTO LEARN PROCEDURE

Use the Manual With the Right Hardware

When to See a Mechanic

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