Programmed 1999-2000 Yukon PCM | 21811787 | VIN Matched

Restore Peak Performance to Your GM Truck or Van

Is your trusty GMC Yukon, Chevy Silverado, or Express van suddenly running rough, shifting erratically, or refusing to start? Before you continue throwing parts at it, the problem might be its electronic brain: the Powertrain Control Module (PCM). As a technician with over two decades of experience, I’ve seen countless vehicles sidelined by a failing PCM. It’s the central command unit for your engine and transmission, and when it falters, it can cause a cascade of frustrating, hard-to-diagnose issues. This isn’t just a replacement part; it’s a direct solution, pre-programmed with the latest GM software specifically for your vehicle’s VIN, ensuring a reliable fix that restores factory operation.

Is Your Vehicle Showing These Telltale Symptoms?

A faulty PCM can manifest in many ways, often mimicking other component failures. Here are the most common signs I’ve diagnosed in my shop that point directly to a needed PCM replacement:

• ✔ Check Engine Light is on with communication-related codes (like P0601, P0605) or random, untraceable misfire codes.
• ✔ The engine cranks but won’t start, or starts and immediately stalls.
• ✔ Noticeably poor fuel economy and sluggish acceleration.
• ✔ Harsh or delayed shifting from the automatic transmission.
• ✔ Intermittent stalling for no apparent reason, especially after warming up.
• ✔ Failure to pass an emissions test due to module-related errors.

The Power of VIN-Specific Programming

Why is providing your VIN so critical? Your vehicle has specific calibrations for its engine, transmission, emissions equipment, and even tire size. Simply installing a generic or junkyard PCM will almost certainly result in a no-start condition or poor performance. We take your VIN and flash this module with the most current, factory-authorized GM software for your exact build. This process ensures all components communicate correctly, giving you optimized fuel delivery, precise ignition timing, and smooth transmission shifts right out of the box. You get the benefit of years of GM software improvements without a trip to the dealership.

Your Straightforward Installation Guide

Replacing the PCM on these GM trucks and vans is a job most DIYers can handle in under an hour. Here’s a simple process to follow:

1. Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes for the system to fully discharge.
2. Locate the PCM: On most trucks (Yukon, Tahoe, Pickups), it’s in the engine bay, typically on the driver’s side fender. On vans (Express, Savana), it’s often in the LH rear of the engine compartment. Check your specific model.
3. Disconnect the Harnesses: The PCM has several large multi-pin connectors. They have locking tabs or levers. Carefully release these and pull the connectors straight out. Never force them.
4. Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware as you may need to reuse it.
5. Install the New Module: Mount your new, pre-programmed PCM onto the bracket and securely tighten the bolts.
6. Reconnect Everything: Firmly plug the wiring harnesses back into the new module until they click into place. Reconnect your negative battery terminal.
7. Final Step: Some vehicles may require a security relearn procedure, which typically involves turning the key to the ‘ON’ position for 10-15 minutes. Consult your vehicle’s service information for any specific relearn steps.

Verified Vehicle Compatibility List

This module is a direct replacement for part numbers 16263494, 16265035, 8162634940, and 218-11787. Please verify your vehicle is on this list and, if noted, that the ID on your original module matches.