Restore Your GM Truck’s Performance and Reliability
Is your 1999 Cadillac Escalade, Chevy Silverado, or GMC Sierra running rough, stalling unexpectedly, or throwing a stubborn check engine light? Before you start replacing sensors and chasing electrical gremlins, it’s time to consider the brain of your engine: the Powertrain Control Module (PCM). As a technician with over two decades of experience under the hood, I’ve seen countless hours and dollars wasted on misdiagnosis when the root cause was a failing PCM. This module is the central command for your engine and transmission, and when it falters, it can create a cascade of frustrating, hard-to-pinpoint issues.
This isn’t just a replacement part; it’s a complete solution. We take the guesswork and the expensive trip to the dealership out of the equation. Each 1999 Escalade PCM is meticulously programmed with the latest official GM software updates, tailored specifically to your vehicle’s Vehicle Identification Number (VIN). This ensures seamless communication with all other modules on your truck, restoring factory performance, shift points, and fuel efficiency. You get a reliable, plug-and-play module ready for installation right out of the box.
Case Study: A Tricky Diagnosis
I remember a ’99 GMC Yukon that came into my bay with an intermittent no-start and a random cylinder misfire that would come and go. The owner had already replaced the fuel pump, spark plugs, and wires. The codes were all over the place. After checking all the wiring and grounds, we hooked up a scope to the injector drivers at the PCM. Sure enough, the signal for cylinder 3 would drop out randomly as the module heated up. A new, correctly programmed PCM fixed everything instantly. It’s a classic example of how a failing computer can send you down the wrong diagnostic path.
Is Your GM Truck or SUV Showing These Signs?
- ✔ Check Engine Light is on with communication or internal module codes (e.g., P0601, P0606, U0100).
- ✔ The engine cranks but refuses to start.
- ✔ Rough or erratic idling and frequent stalling.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or incorrect automatic transmission shifting.
- ✔ Failure to pass an emissions or smog test.
- ✔ No communication with your scan tool.
A Straightforward Guide to Installation
Replacing the PCM on these GM vehicles is a job most DIYers can handle in under an hour with basic hand tools. Follow these steps to get your truck back in top shape.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most of these models, you’ll find the PCM in the engine compartment, typically on the driver’s side fender or near the battery. It’s a silver metal box with multiple large wiring harness connectors.
- Disconnect the Harnesses: Carefully release the locking tabs or levers on each electrical connector and pull them straight out from the module. Avoid pulling on the wires themselves.
- Remove the Old Module: Unbolt the PCM from its mounting bracket. There are usually two or three bolts holding it in place.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and securely tighten the bolts.
- Reconnect Everything: Firmly plug the wiring harnesses back into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn (If Needed): In many cases, you will need to perform a simple security relearn procedure. Turn the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds. Repeat this cycle three times. On the fourth try, the vehicle should start and run normally.
Verified Vehicle Compatibility
This module, identified by part number 16250279 (and interchangeable with 09366810, 09355699), is a direct-fit replacement for the following vehicles. Please match your original part number or contact us with your VIN to confirm compatibility.
- Cadillac Escalade: 1999
- Chevrolet Pickups (1500, 2500, 3500): 1998-1999
- GMC Pickups (1500, 2500, 3500): 1998-1999
- Chevrolet Tahoe / GMC Yukon: 1998-1999
- Chevrolet / GMC Suburban (1500, 2500): 1998-1999
- Chevrolet Astro / GMC Safari Van: 1998-1999
- Chevrolet Express / GMC Savana Van (1500, 2500, 3500): 1998
- Chevrolet S10 / GMC Sonoma: 1998
- Chevrolet Blazer / GMC Jimmy / Oldsmobile Bravada: 1998
- GMC Envoy: 1998
- Isuzu Hombre: 1998
Frequently Asked Questions
How does the programming process work?
After you place your order, simply reply to your confirmation email with your vehicle’s 17-digit VIN. Our technicians will then flash the module with the correct, updated GM software for your specific vehicle before shipping.
Is this a simple plug-and-play installation?
Yes, because the module arrives programmed to your VIN, it is a direct replacement. In most cases, you will only need to perform a simple security relearn procedure, which does not require any special tools.
Will this fix my transmission shifting problems?
The PCM controls both the engine and the transmission. If your shifting issues are caused by faulty electronic commands from the computer, this module is the correct solution. It will restore proper communication and shift logic.
What if my original part number is slightly different?
This module is a direct replacement for part numbers 16250279, 09366810, and 09355699. If your number is different, please contact us with your VIN, and we will verify compatibility for you.
Do I need to send my old PCM back?
No core charge is required for this part. You can keep or recycle your old module.