Restore Peak Performance to Your GM Truck or SUV
Is your trusty 1998-1999 Tahoe, Suburban, or Yukon suddenly acting up? Experiencing frustrating issues like a persistent check engine light, erratic shifting, a rough idle, or even a no-start condition? The problem often points to the vehicle’s brain: the Powertrain Control Module (PCM). As a technician with over two decades of experience under the hood of these GM trucks, I’ve seen firsthand how a failing PCM can cause a cascade of confusing symptoms. This isn’t just a part; it’s the central command center for your engine and transmission.
We’re offering a reliable, tested, and affordable solution. This is a genuine, used OEM PCM, service number 09355699, sourced from a salvaged vehicle. The real value, however, is in our service. Before this module ships, we flash it with the latest GM software updates and program it specifically to your vehicle’s VIN. This means you get a component that is ready to install right out of the box, saving you from a costly trip to the dealership for programming. It’s the most direct path to getting your truck running smoothly again.
A Technician’s Notebook
I remember a ’99 Suburban that came into the shop. The owner had already replaced the fuel pump and ignition coil trying to chase down an intermittent stalling problem. The codes were all over the place. After checking the basics—fuel pressure, spark, and sensor data—I hooked up a scope to the PCM’s main power and ground feeds. Everything looked solid until the engine warmed up, then I saw voltage drops inside the module itself. A failing internal processor was the culprit. We swapped in a VIN-programmed PCM just like this one, and the truck ran perfectly. It’s a classic example of how a faulty 1998-1999 Tahoe PCM can mimic other failures.
Is Your Truck Showing These Telltale Signs?
- ✔ Persistent Check Engine Light (CEL) that won’t go away.
- ✔ Common diagnostic trouble codes (DTCs) like P0601, P0604, or P0606.
- ✔ The engine cranks but refuses to start.
- ✔ Poor or declining fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Stalling, stumbling, or a rough idle, especially when warm.
- ✔ Failing a state emissions inspection.
A Straightforward Guide to Your PCM Swap
Replacing the PCM on these GM trucks is a job most DIYers can handle in their own driveway. Here’s a basic guide to get you started:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait at least 15 minutes for the system capacitors to discharge.
- Locate the PCM: On most of these vehicles, the PCM is located in the engine compartment, typically on the driver’s side fender well or near the battery.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors. These older connectors can be brittle, so take your time. A small flathead screwdriver can help release the locking tabs.
- Remove the Old Module: Unbolt the PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and securely re-attach the wiring harness connectors. You should hear a ‘click’ as they lock into place.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Perform Security Relearn (If Needed): Your vehicle is equipped with a Passlock/VATS security system. You will need to perform a simple 10-minute or 30-minute relearn procedure to sync the new PCM with your key. This involves turning the key to ‘ON’ and waiting, and it requires no special tools. Instructions are widely available online or can be provided.
Verified Fitment for Your GM Vehicle
This module, identified by service number 09355699, is a direct replacement for a wide range of GM trucks, vans, and SUVs. Please verify the number on your original module to ensure a perfect match. Compatible part numbers include: 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, 9366810. This unit fits many vehicles, including:
- ✔ 1998-1999 Chevrolet & GMC Tahoe/Yukon (Gasoline)
- ✔ 1998-1999 Chevrolet & GMC Suburban 1500/2500 (Gasoline)
- ✔ 1998-1999 Chevrolet & GMC C/K 1500, 2500, 3500 Pickups (Gasoline)
- ✔ 1998-1999 Chevrolet Express & GMC Savana 1500, 2500, 3500 Vans (Gasoline)
- ✔ 1999 Cadillac Escalade
- ✔ 1998 Chevrolet Astro & GMC Safari
- ✔ 1998 Chevrolet S10, GMC Sonoma, Oldsmobile Bravada, Isuzu Hombre (4.3L V6)
- ✔ 1998 Chevrolet Blazer & GMC Jimmy (4.3L V6)
Frequently Asked Questions
Do I need to do anything after I install this PCM?
Yes. Because we program the PCM to your VIN, the only remaining step is the security relearn procedure (also known as VATS or Passlock). This syncs the module to your specific key and takes about 10-30 minutes to complete with no special tools required.
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to access the correct GM factory calibration file for your truck’s specific engine, transmission, and emissions equipment. This ensures perfect compatibility and performance.
Is a used PCM reliable?
Absolutely. These OEM modules are robust. We source them from reliable, low-mileage salvaged vehicles and inspect them for any physical damage. The pre-programming service also installs the latest, most stable software from GM, often making it more reliable than the original software it left the factory with.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls both the engine and the transmission. Faulty logic or failing drivers within the module are a very common cause of harsh shifting, delayed engagement, or incorrect gear selection on these models.
How do I find my PCM part number?
Your original PCM will have a large sticker on it with a Service Number (SERV. NO.). This is the number you should match. For this listing, you are looking for ID 09355699 or one of the other compatible numbers listed.