Restore Your Truck’s Brainpower and Performance
Is your 1999-2000 Chevrolet Tahoe or GM truck running rough, stalling unexpectedly, or throwing confusing check engine light codes? The Powertrain Control Module (PCM) is the central computer of your vehicle, managing everything from fuel mixture and spark timing to transmission shifts. When it fails, it can cause a host of frustrating and hard-to-diagnose issues. In my 20+ years as a technician, I’ve seen hundreds of these GMT400 and early GMT800 platform trucks sidelined by a faulty PCM. Symptoms that seem like a bad sensor or fuel pump often trace back to this critical component.
This isn’t just a replacement part; it’s a complete, plug-and-play solution. We take the guesswork and dealer hassle out of the equation. Each 1999-2000 Tahoe PCM is professionally programmed with the latest GM software updates specifically for your vehicle using the VIN you provide. This ensures perfect communication between all your vehicle’s systems, restoring the smooth operation and reliability you depend on.
From the Diagnostic Bay: The Suburban That Wouldn’t Start
A customer brought in his ’99 Suburban 1500, a vehicle I know like the back of my hand. The complaint was an intermittent no-start. It had spark, it had fuel pressure, but it would just crank and crank. He’d already replaced the fuel pump and crank sensor. After hooking up my scan tool, I noticed the PCM wasn’t commanding the injectors to fire consistently. On a hunch, I checked for internal processor error codes and found a pending P0601. The original PCM was failing internally. Instead of a costly trip to the dealer for a new module and programming, we ordered one of these pre-programmed units. It arrived, we swapped it in 15 minutes, and the truck fired up on the first try. The customer was back on the road the same day, problem solved.
Is Your Truck Showing These Signs of a Bad PCM?
- ✔ Unexplained Check Engine Light with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- ✔ Engine stalling, misfiring, or running rough for no apparent reason.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ A no-start condition even with good fuel pressure and spark.
- ✔ Noticeable decrease in fuel economy.
- ✔ Failure to pass an emissions/smog test.
- ✔ Communication errors with diagnostic scan tools.
Simple Swap: Your PCM Installation Guide
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- ✔ Locate the PCM: On most 1999-2000 Tahoes, Yukons, and pickups, the PCM is located in the engine compartment on the driver’s side, often near the fender or firewall. On vans, it’s typically in the LH rear of the engine compartment.
- ✔ Disconnect the Harnesses: Carefully unplug the electrical connectors from the old module. There are typically release tabs that need to be pressed or lifted. Do not force them.
- ✔ Remove the Old Module: Unbolt the PCM from its mounting bracket. Keep the hardware as you will need it for the new module.
- ✔ Install the New Module: Mount your new, pre-programmed PCM onto the bracket and securely fasten it.
- ✔ Reconnect Everything: Plug the wiring harnesses firmly into the new module until they click into place. Reconnect the negative battery terminal.
- ✔ Perform Security Relearn (If Needed): In many cases, you may need to perform a simple security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times. This allows the new PCM to sync with your vehicle’s anti-theft system.
Verified Fitment for Your GM Vehicle
This module is a direct-fit replacement for a wide range of GM trucks, vans, and SUVs. It is compatible with part numbers 16263494, 16265035, and 8162634940. Please verify your part number or use the compatibility list below. After purchase, simply provide your VIN, and we’ll handle the programming to ensure it’s a perfect match.
Fitment includes, but is not limited to: Chevrolet Tahoe (99-00), Suburban (99), Silverado/GMC Sierra (99-00), S10/Sonoma (98-00), Blazer/Jimmy (98-00), Astro/Safari (99-01), Express/Savana Vans (99-02), Cadillac Escalade (99-00), and more. Please check the detailed list to confirm your specific model and engine.
Frequently Asked Questions
How does the VIN programming work?
After you complete your purchase, you will need to send us your vehicle’s 17-digit VIN. Our technicians use this number to access the latest official GM software for your exact vehicle configuration. We then flash this software onto the module before shipping it to you.
Is this module difficult to install?
No, this is a straightforward DIY job for anyone with basic mechanical skills. It’s a direct swap that typically requires only simple hand tools. No complex programming equipment is needed on your end.
Will this fix my check engine light?
If the check engine light is caused by a faulty PCM (e.g., codes P0601, P0604, P0606), this replacement module will solve the problem. It’s always best to have your vehicle properly diagnosed to confirm the PCM is the root cause before ordering.
What if my original part number isn’t listed?
The part numbers 16263494, 16265035, and 8162634940 are the most common for this family of PCMs. If your number is different, please contact us with your VIN, and we can verify compatibility for you.
Do I need to do a security relearn procedure?
Yes, on most of these GM vehicles, a security relearn (also known as a CASE relearn or Passlock relearn) is required after installation. It is a simple procedure that does not require any special tools and instructions are readily available online or can be provided.