Restore Your GM Truck’s Core Performance and Reliability
As a technician with over two decades of experience, I’ve seen firsthand how a failing Powertrain Control Module (PCM) can turn a dependable truck into a source of constant frustration. If your 1999-2000 GMC Yukon, or a similar GM vehicle, is experiencing baffling issues like stalling, erratic shifting, a persistent check engine light, or poor fuel economy, the PCM is often the culprit. This isn’t just a part; it’s the central computer managing your engine’s performance, and when it falters, everything is affected.
We solve this problem by providing a high-quality replacement PCM, part number 16265035, that arrives at your door ready for installation. The biggest hurdle for any DIYer or even a professional shop is programming. We eliminate that step entirely. Simply provide us with your vehicle’s VIN during checkout, and our experts will flash the module with the latest, most stable software updates directly from GM. This ensures perfect compatibility and optimal function, saving you a costly trip to the dealership and the hassle of specialized tools.
A Technician’s Notebook
I remember a 2000 GMC Yukon Denali that came into the bay with a complaint of intermittent stalling at stoplights and a check engine light that previous shops couldn’t solve. The codes were all over the place—random misfires, O2 sensor faults, and a dreaded P0601 (Internal Control Module Memory Check Sum Error). After verifying the wiring and grounds were solid, we knew it was the PCM. The owner was worried about the high cost of a new, dealer-programmed unit. We installed one of our VIN-flashed modules, performed the security relearn, and the truck ran like it just rolled off the assembly line. It’s a common failure, and having a pre-programmed solution is a game-changer.
Is Your Truck Showing These Warning Signs?
A failing PCM can manifest in numerous ways. If you’re noticing any of the following, it’s a strong indicator that the brain of your engine needs attention.
- ✔ Check Engine Light is illuminated with codes like P0601, P0604, or P0606.
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel efficiency.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Stalling for no apparent reason, especially when warm.
- ✔ Failure to pass state emissions testing.
A Straightforward Guide to Installation
Installing your new 1999-2000 Yukon PCM is a manageable job for a confident DIYer. Follow these steps carefully for a smooth replacement. Note: After installation, a security relearn procedure (often called a CASE relearn) is typically required. This can usually be done without special tools and instructions are widely available online for your specific vehicle.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most of these trucks and vans, the PCM is located in the engine compartment, often on the driver’s side fender well or near the battery.
- Disconnect the Connectors: Carefully unclip the wiring harness connectors from the old module. These connectors have locking tabs that may need to be gently pried or squeezed to release. Inspect them for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. It’s typically held in place by a few bolts or nuts.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and secure it.
- Reconnect Everything: Firmly plug the wiring harness connectors into the new PCM until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: Start the vehicle. You will likely need to perform the security relearn procedure to sync the new PCM with your vehicle’s anti-theft system. This often involves a sequence of turning the key on and off.
Verified Compatibility for Your Vehicle
This module is a direct replacement for part numbers 16263494, 16265035, 8162634940, 218-11787, and 21811787. It is confirmed to fit a wide range of GM trucks and vans. Please verify your vehicle is on the list below. Providing your VIN is essential for us to ensure 100% correct programming.
Frequently Asked Questions About the 1999-2000 Yukon PCM
Frequently Asked Questions
Do I need to do any programming myself?
No. This module arrives fully programmed to your vehicle’s specific VIN with the latest GM software. The only additional step you may need to perform is a simple security relearn procedure, which does not require any special tools.
What is a ‘CASE Relearn’ and is it required?
A Crankshaft Variation Relearn (CASE) syncs the PCM with the crankshaft position sensor. While not always mandatory for the vehicle to run, it is highly recommended for optimal performance and to prevent a future check engine light. Many high-end consumer scan tools can perform this, or a local shop can do it quickly.
How do I provide my VIN?
After you complete your purchase, you will receive instructions on how to send us your 17-digit Vehicle Identification Number (VIN). We cannot ship your part until we receive this information, as it’s essential for the programming process.
Will this fix my vehicle’s problem for sure?
This PCM will correct issues directly caused by a faulty module. While the symptoms listed are very common for PCM failure, it’s always best practice to have a proper diagnosis performed to rule out other potential issues like bad sensors or wiring problems.
What if my original part number is not 16265035?
This module is also a direct replacement for several other part numbers, including 16263494 and 8162634940. As long as your vehicle is on the compatibility list and you provide a valid VIN, we will ensure the programming is a perfect match for your application.