Restore Your Van’s Brain and Get Back on the Road with Confidence
Is your 1998-1999 GMC Safari or Astro van acting possessed? Dealing with frustrating issues like stalling at stoplights, erratic shifting, a persistent Check Engine Light, or a no-start condition can make you lose faith in your trusty workhorse. Before you spend a fortune at the dealership, consider the root cause: a failing Powertrain Control Module (PCM). This module is the central computer for your engine and transmission, and when it goes, it can create a cascade of baffling problems. This isn’t just an inconvenience; it’s a reliability issue that can leave you stranded.
We offer a straightforward, reliable solution. This Powertrain Control Module is a direct-fit replacement for service part number 16250279. The best part? We handle the complicated part for you. Simply provide your vehicle’s VIN during checkout, and our technicians will flash the module with the latest, most stable GM-certified software specific to your van. This eliminates the need for expensive dealer programming, making this a true plug-and-play fix for both professional mechanics and determined DIYers.
A Technician’s Notebook: The Ghost in the Machine
I remember a 1999 Safari that came into my bay with a complaint that stumped two other shops. The owner said it would randomly lose power and the transmission would get stuck in gear, but there were no consistent trouble codes—just a random assortment of communication errors. After checking all the wiring and grounds, which looked perfect, I focused on the PCM. On these older GM vans, the PCM is located right by the battery, where it’s exposed to heat, vibration, and potential acid fumes. Over 20 years, this environment takes its toll on the delicate internal circuits. We swapped in a pre-programmed PCM, and the van ran perfectly. It’s a classic case where the symptoms seem complex, but the solution is replacing the aging brain of the vehicle.
Is Your GMC Safari Showing These Symptoms?
- ✔ Unexplained Check Engine Light with codes like P0601 (Internal Control Module Memory Check Sum Error) or other P06xx processor faults.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ The engine cranks but refuses to start.
- ✔ A noticeable drop in fuel economy.
- ✔ Stalling, stumbling, or hesitation during acceleration.
- ✔ Communication errors with your scan tool.
A Straightforward Guide to Installation
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- ✔ Locate the PCM: On your GMC Safari, the PCM is typically located in the engine compartment on the driver’s side, near the battery.
- ✔ Disconnect Connectors: Carefully unclip the wiring harness connectors from the old module. These connectors have locking tabs that need to be released before pulling.
- ✔ Remove the Old Module: Unbolt the old PCM from its mounting bracket. It’s usually held in by a few small bolts.
- ✔ Install the New Module: Mount your new, pre-programmed PCM onto the bracket and securely fasten the bolts.
- ✔ Reconnect Everything: Plug the wiring harness connectors firmly into the new module until they click into place. Reconnect the negative battery terminal.
- ✔ Final Check: Start the vehicle. It may take a moment to idle smoothly as it completes its initial learning cycle. The Check Engine Light should be off, and your van should run smoothly.
Verified Vehicle Compatibility
This module, identified by part number 16250279, is a direct replacement for many GM trucks, vans, and SUVs. It also interchanges with part numbers 09366810 and 09355699. Please verify your original part number or consult the list below. This part fits:
Chevrolet & GMC Pickups (1500/2500/3500) (1998-1999): Gasoline engines, check for ID 16250279
Chevrolet Tahoe / GMC Yukon (1998-1999): Gasoline engines, (LH engine compartment)
Chevrolet Suburban (1500/2500) (1998-1999): Gasoline engines, (LH engine compartment)
Cadillac Escalade (1999): (LH front engine compartment)
Chevrolet Express / GMC Savana (1500/2500/3500) (1998): Gasoline engines
Chevrolet S10 / GMC Sonoma / Oldsmobile Bravada / Isuzu Hombre (1998): 4.3L V6, check for specific build options and ID numbers 16250279 or 16258815.
Chevrolet Blazer / GMC Jimmy / GMC Envoy (1998): Check for specific build options and ID numbers 16250279 or 16258815.
Note: Always match your original part number for guaranteed compatibility.
Frequently Asked Questions About Your 1998-1999 GMC Safari PCM
Frequently Asked Questions
Do I need to do any programming myself?
No. This PCM arrives at your door fully programmed to your vehicle’s specific VIN. It’s ready for installation right out of the box, saving you a trip to the dealership.
What information do you need from me?
After you complete your purchase, we will need the 17-digit Vehicle Identification Number (VIN) from your GMC Safari. This ensures we load the correct factory software for your engine, transmission, and options.
Is this a simple DIY job?
For most individuals with basic hand tools, this is a very manageable repair. The module is typically easy to access in the engine bay, and since no programming is required, it’s a matter of unplugging the old unit and plugging in the new one.
How do I find my original part number?
The service part number is printed on a sticker on the case of your current PCM. You will need to locate and likely remove the module to read it. Matching the number to 16250279, 09366810, or 09355699 ensures a perfect match.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls both engine and transmission functions. Faulty signals from a failing module are a very common cause of poor shifting, delayed engagement, and other transmission-related issues on these vehicles.