Restore Your Truck’s Brain and Get Back on the Road
Is your trusty 1998 or 1999 GMC Suburban 2500 suddenly unreliable? If you’re dealing with frustrating no-start conditions, stalling, a persistent Check Engine Light, or bizarre electrical behavior, the problem often points directly to a failing Powertrain Control Module (PCM). As the central computer, when the PCM goes, it can create a cascade of issues that are difficult to diagnose. I’ve seen it countless times in my shop: mechanics and DIYers chase ghosts, replacing perfectly good sensors, when the core issue was the vehicle’s computer all along.
This isn’t just a replacement part; it’s a direct solution. We offer a dependable, tested, and correctly functioning OEM PCM, part number 9355699, sourced from a salvaged vehicle. The critical difference is our service: before this module ships, we flash it with the latest GM-certified software, specifically programmed to your vehicle’s unique VIN. This ensures seamless communication between the engine, transmission, and all related systems, restoring the performance and reliability you depend on.
From the Diagnostic Bay
I remember a ’99 Tahoe that came in on a tow truck. The owner had replaced the fuel pump, ignition coil, and crank sensor trying to solve an intermittent stalling problem. It would run fine for 20 minutes, then die without warning and refuse to restart for an hour. No consistent codes. After checking fuel pressure and spark during a failure, everything seemed fine. On a hunch, I monitored the PCM’s data stream. Just before it stalled, the data went haywire. The PCM was failing internally as it heated up. We installed a VIN-programmed module just like this one, and the truck has been running solid for years. This part solved a problem that had cost the owner hundreds in unnecessary repairs.
Is Your GM Truck or Van Showing These Telltale Signs?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, this module is the likely solution for your 1998-1999 Suburban 2500 PCM issues:
- ✔ Check Engine Light is on with internal processor codes like P0601, P0605, or P0606.
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling, especially after the engine has warmed up.
- ✔ Rough idling or poor engine performance.
- ✔ Noticeably worse fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to pass an emissions/smog test.
A Straightforward Guide to Your PCM Swap
One of the biggest benefits of our service is that the programming is already done. This makes the physical installation a job most DIYers can handle in their own driveway. Here’s a general guide:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait a few minutes before starting work.
- Locate the PCM: On most of these GM trucks and SUVs, the PCM is located in the engine compartment, typically on the driver’s side fender well or near the firewall.
- Disconnect the Harnesses: Carefully unclip and disconnect the large electrical wiring harnesses from the old PCM. These connectors have locking tabs; be gentle to avoid breaking them.
- Remove the Old Module: Unbolt the 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: Firmly plug the wiring harnesses back into the correct slots on the new PCM. You should hear a ‘click’ as they lock into place. Reconnect the negative battery terminal.
- Final Step (If Needed): In many cases, the vehicle will start and run perfectly. However, some GM vehicles of this era require a security relearn procedure (often called PASS-Key or Passlock) to allow the engine to start. This procedure is simple and involves turning the key to specific positions for set amounts of time. It does not require a special scan tool.
Verified Fitment for a Wide Range of GM Vehicles
This module, identified by service number 9355699, is a direct replacement for a vast array of GM trucks, vans, and SUVs. It is compatible with multiple part numbers, including 16266645, 16250279, 16258815, and 09366810. Please verify your vehicle is on the list below and that your original module carries the ID 9355699 for guaranteed compatibility.
CHEVROLET 2500 PICKUP 98-99 (Gasoline)
CHEVROLET 3500 PICKUP 98-99 (Gasoline)
GMC 1500 PICKUP 98-99 (Gasoline)
GMC 2500 PICKUP 98-99 (Gasoline)
GMC 3500 PICKUP 98-99 (Gasoline)
SUBURBAN 1500/2500 98-99 (Gasoline)
TAHOE/YUKON 98-99 (Gasoline)
ESCALADE 99
EXPRESS/SAVANA VAN 1500/2500/3500 98-99 (Gasoline)
ASTRO/SAFARI VAN 98
BLAZER S10/JIMMY S15 98 (w/o build date opt ZN4)
S10/S15/SONOMA 98 (4.3L, w/o build date opt ZN4)
BRAVADA 98 (w/o build date opt ZN4)
ENVOY 98 (w/o build date opt ZN4)
ISUZU HOMBRE 98 (4.3L, w/o extended build date opt ZN4)
Frequently Asked Questions
Why do you need my VIN?
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential. It allows us to access the specific GM database for your truck’s original equipment, including engine size, transmission type, and emissions components. We use this to load the correct factory software and the latest updates onto the PCM, ensuring it works perfectly with your vehicle right out of the box.
Is a used PCM reliable?
Absolutely. We source these modules from salvaged vehicles and put them through a rigorous testing process to ensure full functionality. OEM (Original Equipment Manufacturer) electronics are built to a very high standard. A tested, used OEM part is often more reliable than a low-quality aftermarket alternative. It’s a cost-effective way to get a genuine GM part.
Will I need to do anything else after installation?
Because this PCM comes pre-programmed to your VIN, no dealer programming is required. However, some GM vehicles from this era may require a simple ‘Security Relearn Procedure’ to sync the new PCM with the vehicle’s anti-theft system. This can be done at home without any special tools and instructions are widely available online or in service manuals.
What is the difference between a PCM and an ECM?
The terms are often used interchangeably. ECM stands for Engine Control Module, while PCM stands for Powertrain Control Module. In most modern vehicles like your Suburban, the module controls both the engine and the transmission, making ‘PCM’ the more accurate term. For this part, both terms refer to the same computer.