Restore Peak Performance to Your GM Truck or SUV
If you’re dealing with frustrating, hard-to-diagnose issues on your 1998-1999 GMC Yukon or a similar GM vehicle, the Powertrain Control Module (PCM) is often the culprit. As a technician with over two decades of experience under the hood, I’ve seen firsthand how a failing engine computer can cause a cascade of problems that seem unrelated. This isn’t just a part; it’s the central command center for your engine and transmission. Our reliable, tested PCM, part number 16266645, is the definitive solution to get your truck running right again.
What sets this module apart is our professional programming service. Before we ship it, we flash the unit with the latest GM software updates, specifically matched to your vehicle’s VIN. This eliminates the need for an expensive trip to the dealership for programming. You get a component that’s ready for installation right out of the box, saving you significant time, money, and hassle. This is the smart, efficient fix for both seasoned mechanics and dedicated DIYers.
Case Study: A Tricky Diagnosis
I remember a ’99 Tahoe that came into the shop with a complaint of intermittent stalling and a random no-start condition. The owner had already replaced the fuel pump and ignition coil with no luck. The scan tool showed no hard codes, just a history of communication loss faults. After checking all the primary power and ground circuits to the PCM, we connected a lab scope. We found the 5-volt reference signal, which powers critical sensors, was erratically dropping out. This pointed directly to an internal failure in the original 1998-1999 Yukon PCM. We installed one of our pre-programmed units, performed the security relearn, and the truck ran perfectly. It’s a classic example of how a failing PCM can create ghost-like symptoms that defy simple parts-swapping.
Is Your Truck Showing These Symptoms?
A failing PCM can manifest in numerous ways. If you’re experiencing any of the following, this module is likely the solution you need:
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
- ✔ Vehicle refuses to start or has a long crank time.
- ✔ Rough or erratic engine idle.
- ✔ Harsh or unpredictable transmission shifting.
- ✔ A noticeable drop in fuel economy.
- ✔ Stalling for no apparent reason.
- ✔ Failure to communicate with a diagnostic scan tool.
A Straightforward Guide to Installation
Replacing your 1998-1999 Yukon PCM is a manageable job for most DIYers. Follow these steps carefully for a smooth installation.
- Safety First: Disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent accidental contact.
- Locate the PCM: On most of these trucks and vans (including the Yukon, Tahoe, and pickups), the PCM is located in the engine compartment on the driver’s side, near the firewall or inner fender.
- Disconnect the Connectors: Carefully unclip and remove the electrical harness connectors from the old PCM. There are typically three or four large multi-pin connectors. Inspect them for any corrosion or damage.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and securely re-fasten the bolts.
- Reconnect Everything: Firmly plug the harness connectors into the new PCM until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: This is a critical step. Turn the key to the ‘ON’ position (do not start) for 10-15 minutes. The security light should turn off. Turn the key off for 10 seconds, then repeat this cycle two more times. After the third cycle, the vehicle should start and run normally.
Verified Vehicle Compatibility
This PCM is a direct replacement for multiple part numbers and fits a wide range of GM vehicles. Please ensure your vehicle is on this list and that the service ID number on your original module matches. This unit replaces part numbers: 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, and 9366810.
This module is compatible with, but not limited to, the following models (with matching ID 9355699):
- 1998-1999 GMC Yukon / Chevrolet Tahoe
- 1998-1999 GMC / Chevrolet Suburban 1500 & 2500 (Gasoline)
- 1998-1999 GMC / Chevrolet C/K 1500, 2500, 3500 Pickups (Gasoline)
- 1999 Cadillac Escalade
- 1998-1999 GMC Savana / Chevrolet Express Vans (1500, 2500, 3500 Gasoline)
- 1998 Oldsmobile Bravada / GMC Envoy
- 1998 Chevrolet S10 / GMC Sonoma (4.3L)
- 1998 Chevrolet Blazer / GMC Jimmy (4.3L)
- 1998 GMC Safari / Chevrolet Astro
- 1998 Isuzu Hombre (4.3L)
How do I provide my VIN?
How do I provide my VIN?
After you complete your purchase, simply reply to your order confirmation email with your vehicle’s 17-digit VIN, or send it to us through our contact form with your order number. We cannot ship the module until we have this information.
Is any other programming required after installation?
Our programming handles the engine and transmission operating systems. However, you will need to perform the simple Security Relearn Procedure (detailed in the installation guide) to sync the module with your vehicle’s anti-theft system. No special tools are required for this.
Is this a new part?
This is a high-quality, fully tested used PCM sourced from a salvaged vehicle. Each unit is inspected for integrity and then professionally programmed with the latest GM software for your specific VIN, ensuring reliable operation.
What if my original part number isn’t 16266645?
This module is a direct replacement for several part numbers, including 09355699, 16250279, and others listed above. As long as your vehicle is on the compatibility list and your original module has the ID 9355699, this part will work correctly.