Restore Peak Performance to Your GM Truck or Van
If you’re dealing with a frustrating check engine light, poor fuel mileage, erratic shifting, or a no-start condition in your 1999 Chevrolet Suburban 2500, the root cause is often a failing Powertrain Control Module (PCM). As the central computer of your vehicle, the PCM is responsible for managing everything from fuel delivery and spark timing to transmission shifts. When it falters, the entire vehicle suffers. This isn’t just an inconvenience; it can leave you stranded. For over 20 years, I’ve seen countless GM trucks and vans sidelined by these exact issues, and a reliable replacement PCM is the definitive solution.
This module is the answer. It arrives at your door fully programmed with the latest GM software updates, specifically matched to your vehicle’s VIN. This means no expensive trips to the dealership for programming. It’s a direct-fit, plug-and-play solution designed to get your reliable workhorse back on the road quickly and affordably. We take the guesswork out of the repair so you can focus on the simple installation.
Is Your GM Vehicle Showing These Symptoms?
- ✔ Persistent Check Engine Light (CEL)
- ✔ Diagnostic Trouble Codes (DTCs) like P0601 (Internal Memory Error) or P0606 (PCM Processor Fault)
- ✔ Vehicle won’t start or stalls intermittently
- ✔ Harsh or incorrect automatic transmission shifting
- ✔ Noticeable decrease in fuel economy
- ✔ Failure to pass state emissions testing
- ✔ Communication errors with diagnostic scan tools
A Technician’s Notebook
I remember a 1999 Chevy K2500 that came into my shop with a maddeningly intermittent no-start condition. The owner had already replaced the battery, starter, and fuel pump. The truck would run fine for days, then refuse to start for no apparent reason. After hooking up my scope, I noticed the injector pulse and spark control signals were dropping out randomly. The culprit? The original PCM was failing internally due to heat cycles over two decades. We installed one of these VIN-programmed modules, performed the quick security relearn, and the truck fired up every single time. It’s a classic failure on these GMT400 platforms, and having a pre-programmed unit turned a multi-hour diagnostic headache into a simple, profitable one-hour job.
A Straightforward Guide to 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 trucks like the Suburban or Silverado, the PCM is located in the engine compartment on the driver’s side, near the fender or firewall. On vans like the Express/Savana, it’s often in the rear of the engine compartment.
- ✔ Disconnect the Harnesses: Carefully unclip and remove the electrical connectors from the old PCM. These connectors have locking tabs; be gentle to avoid breaking them.
- ✔ Remove the Old Module: Unbolt the old PCM from its mounting bracket. It’s typically 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 electrical harnesses back into the new PCM until they click firmly into place. Reconnect the negative battery terminal.
- ✔ Perform Security Relearn (If Needed): In many cases, you will need to perform a security or CASE (Crankshaft Angle Sensor Error) relearn procedure. This can often be done without special tools by cycling the key. A quick search for your specific model’s “security relearn procedure” will provide the exact steps. This synchronizes the new PCM with your vehicle.
Will This Fit My Vehicle?
This Powertrain Control Module is a direct replacement for a wide range of GM trucks, SUVs, and vans. Please verify your part number or match your vehicle from the list below. This module is compatible with service numbers: 16263494, 16265035, 8162634940, 218-11787, and 21811787.
CHEVROLET 3500 PICKUP 99-00 (gasoline)
CHEVROLET 1500 PICKUP 99 (5.0L/5.7L, ID 16263494)
SILVERADO 1500 PICKUP 99-00 (4.3L V6)
SUBURBAN 1500/2500 99 (gasoline, ID 16263494)
TAHOE 99-00 (gasoline, ID 16263494 for ’99)
S10 PICKUP 98-00 (4.3L)
BLAZER/JIMMY 98-00 (4.3L)
ASTRO VAN 99-01 (ID 16263494)
EXPRESS/SAVANA VAN 1500/2500/3500 99-02 (gasoline)
GMC 1500/2500/3500 PICKUP 99-00 (gasoline)
SIERRA 1500 PICKUP 99-00 (4.3L V6)
YUKON/DENALI 99-00 (ID 16263494 for ’99)
SAFARI VAN 99-01 (ID 16263494)
CADILLAC ESCALADE 99-00
OLDSMOBILE BRAVADA 98-00 (4.3L)
GMC ENVOY 98-00
ISUZU HOMBRE 98-00 (4.3L)
Note: Some 1998 models require build date option ZN4. Please verify fitment.
Frequently Asked Questions
Frequently Asked Questions
Do I need to do anything after I install it?
Because this PCM comes pre-programmed to your VIN, no dealer flashing is required. However, you will likely need to perform a simple security relearn procedure, which syncs the module to your vehicle’s anti-theft system. This can usually be done in your driveway by cycling the ignition key.
How do I provide my VIN?
After you complete your purchase, simply send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship the module without it.
Is this compatible with my existing part number?
Yes, this module is a direct replacement for several part numbers, including 16263494, 16265035, and 8162634940. If your original module has one of these numbers, this part will work for you.
What happens if I don’t perform the CASE relearn?
The Crankshaft Angle Sensor Error (CASE) relearn synchronizes the PCM with the crankshaft position sensor. If it’s not performed, you may have a persistent check engine light with code P1336. The vehicle will still run, but it won’t be operating at peak efficiency.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls transmission line pressure and shift points. If the module’s internal drivers or logic have failed, it can cause harsh shifting, slipping, or failure to shift. A new PCM often resolves these electronic-based transmission issues.