Restore Your Truck’s Brain and Get Back on the Road
As a technician with over two decades of experience, I’ve seen firsthand how a failing Powertrain Control Module (PCM) can bring even the toughest trucks to a dead stop. If your 1998-1999 Chevrolet 3500 Pickup is experiencing perplexing issues like erratic shifting, a persistent check engine light, stalling, or a complete no-start condition, the PCM is a primary suspect. This isn’t just a part; it’s the central computer responsible for engine performance, fuel management, and transmission control. A faulty one can cause headaches for DIYers and professional mechanics alike.
We offer a dependable and straightforward solution: a quality-inspected, used OEM PCM, part number 16258815. The most significant benefit we provide is our professional programming service. Before this module ships, we flash it with the latest GM-certified software updates, tailored specifically to your vehicle’s Vehicle Identification Number (VIN). This critical step ensures the PCM communicates perfectly with your truck’s systems, restoring original performance and efficiency. You get a part that is ready for installation right out of the box, saving you from costly dealership programming fees and vehicle downtime.
A Technician’s Notebook
I remember a 1999 GMC Savana 3500 work van that came into the shop. The owner, a plumber, was losing business because the van would randomly stall at traffic lights and occasionally refuse to start in the morning. He had already replaced the fuel pump and ignition coil with no success. After hooking up my scan tool, I pulled a P0601 code – “Internal Control Module Memory Check Sum Error.” This code points directly to a fatal flaw within the PCM itself. Instead of a costly, back-ordered dealer part, we sourced a compatible used module like this one. We programmed it to his van’s VIN, performed the security relearn, and had him back on the road that same afternoon. He called a week later, thrilled that his workhorse was running reliably again. This is the exact type of dependable fix we aim to provide for your vehicle.
Is Your Truck Showing These Symptoms?
A failing PCM can manifest in various ways. If you’re experiencing any of the following, this module is the likely solution for your 1998-1999 Chevrolet 3500 PCM issues:
- ✔ Unexplained Check Engine Light (CEL)
- ✔ Diagnostic Trouble Codes (DTCs) like P0601, P0605, or other communication errors.
- ✔ Engine stalling, stumbling, or rough idling.
- ✔ Complete no-start condition where the engine cranks but won’t fire.
- ✔ Poor or inconsistent automatic transmission shifting.
- ✔ Noticeable decrease in fuel economy.
- ✔ Failure to pass state emissions testing.
A Straightforward Guide to Installation
Installing your programmed 1998-1999 Chevrolet 3500 PCM is a manageable job for a confident DIYer. Follow these general steps to ensure a smooth process:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most of these trucks and vans, the PCM is located in the engine compartment, typically on the driver’s side fender well or firewall.
- Disconnect Connectors: Carefully unplug the wiring harness connectors from the old PCM. These connectors have locking tabs that may need to be gently pried or squeezed to release. Inspect the connectors for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware as you will need it for the new module.
- Install the New Module: Mount your new, pre-programmed PCM onto the bracket and securely fasten it.
- Reconnect Everything: Firmly plug the wiring harness connectors into the new module until they click into place. Reconnect the negative battery terminal.
- Perform Security Relearn: Your vehicle may require a security relearn procedure (often called a Passlock or VATS relearn) to recognize the new PCM. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times before attempting to start the engine. Consult your vehicle’s service manual for the exact procedure.
Verified Vehicle Compatibility
This Electronic Control Module is a direct replacement for service number 16258815 and is interchangeable with part numbers 09355699, 16266645, 9355699, 16250279, and 09366810. It is confirmed to fit a wide range of GM vehicles. Please match your part number or verify fitment with the list below:
- ASTRO 98 (LH front by battery)
- BLAZER S10/JIMMY S15 98 (RH front engine compartment)
- BRAVADA 98 (4.3L)
- CHEVROLET 1500 PICKUP 98-99 (Gasoline)
- CHEVROLET 2500 PICKUP 98-99 (Gasoline)
- CHEVROLET 3500 PICKUP 98-99 (Gasoline)
- ENVOY 98 (RH front engine compartment)
- ESCALADE 99 (LH front engine compartment)
- EXPRESS 1500 VAN 98-99
- EXPRESS 2500 VAN 98-99 (Gasoline)
- EXPRESS 3500 VAN 98-99 (Gasoline)
- GMC 1500 PICKUP 98-99 (Gasoline)
- GMC 2500 PICKUP 98-99 (Gasoline)
- GMC 3500 PICKUP 98-99 (Gasoline)
- ISUZU HOMBRE 98 (4.3L)
- S10/S15/SONOMA 98 (4.3L)
- SAFARI (GMC) 98 (LH front by battery)
- SAVANA 1500 VAN 98-99
- SAVANA 2500 VAN 98-99 (Gasoline)
- SAVANA 3500 VAN 98-99 (Gasoline)
- SUBURBAN 1500 98-99 (Gasoline)
- SUBURBAN 2500 98-99 (Gasoline)
- TAHOE 98-99 (Gasoline)
- YUKON 98-99
Frequently Asked Questions
What does ‘VIN Programmed’ mean for me?
It means we load your vehicle’s specific VIN into the module before shipping. This ensures it has the correct software for your engine, transmission, and options, making the installation process much smoother and often avoiding a trip to the dealer.
Do I need to do anything after I install it?
In most cases, you will need to perform a simple security relearn procedure (also known as a VATS or Passlock relearn). This allows your vehicle’s anti-theft system to synchronize with the new PCM. The procedure is straightforward and can be done without special tools.
Is this a new part?
No, this is a high-quality, tested used OEM part sourced from a salvaged vehicle. We inspect and program it with the latest GM software to ensure it provides reliable service as a cost-effective alternative to a new module.
How do I find my PCM’s part number?
The part number is printed on a sticker on the PCM itself. You will need to locate the module on your vehicle (typically in the engine bay) and read the service number from the label.
What happens after I purchase?
After you complete your purchase, you must provide us with your 17-digit VIN. We cannot program or ship the module without it. This ensures you receive a part that is correctly configured for your exact vehicle.