Get Your Workhorse Back on the Road with a Reliable, Programmed PCM
As a technician with over two decades of experience, I’ve seen countless hardworking GM trucks and vans from the late ’90s sidelined by a failing Powertrain Control Module (PCM). One minute your 1999 Savana is running perfectly, the next it’s stalling, shifting erratically, or refusing to start at all. It’s frustrating, especially when your livelihood depends on your vehicle. The PCM is the electronic brain of your engine and transmission, and when it fails, it can cause a cascade of confusing problems. This isn’t just a part; it’s the command center for your vehicle’s performance and reliability.
We offer a straightforward and dependable solution: a quality-tested, used OEM PCM that is professionally programmed to your vehicle’s specific Vehicle Identification Number (VIN). Forget expensive dealership visits and the hassle of finding a shop that can program older modules. This unit arrives at your door with the latest GM software updates already installed, making the repair process as simple as possible. This is the most efficient way to solve those nagging electronic gremlins and restore the dependable performance you expect from your GM vehicle.
Case Study: The No-Start 1999 Express Van
A local contractor brought in his ’99 Express 3500 work van that would crank but not start. He had already replaced the fuel pump and the ignition control module based on advice from forums, but the problem persisted. My scan tool couldn’t communicate with the PCM—a classic red flag. After checking the power and ground feeds to the module, which were all good, I knew the PCM itself was the culprit. In my shop, I’ve seen this exact scenario dozens of times. We installed one of our VIN-programmed PCMs, performed the quick security relearn, and the van fired right up on the first try. He was back on the job site the same afternoon, saving hundreds compared to a dealership repair.
Is Your GM Truck or Van Showing These Signs?
A failing PCM can manifest in various ways. If you’re experiencing any of the following, a faulty module could be the root cause:
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (PCM Processor Fault).
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained stalling or rough, inconsistent idling.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Your scan tool cannot communicate with the computer.
- ✔ Intermittent issues that seem to have no other logical cause.
A Straightforward Guide to Your PCM Swap
Replacing the PCM in these GM vehicles is a job most DIYers can handle with basic tools. Our pre-programmed module simplifies the process significantly. While a security relearn procedure is required after installation, it doesn’t require any special tools. Here’s a general guide:
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- 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 or near the battery.
- Disconnect the Connectors: Carefully unclip and remove the wiring harness connectors from the old PCM. Inspect them for any corrosion or damage.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount your new, programmed PCM into the bracket and securely re-attach the wiring harness connectors.
- Reconnect the Battery: Re-attach the negative battery terminal.
- Perform Security Relearn: You will need to perform the GM Passlock/VATS security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating this cycle three times. Your vehicle will not start until this is completed.
Verified Vehicle Compatibility List
This PCM, identified by service ID 9355699, is a direct replacement for multiple part numbers, including 09355699, 16266645, 16250279, 16258815, and 9366810. It is guaranteed to fit the following GM, Chevrolet, and Isuzu models from 1998-1999. Please match the ID number from your original module to ensure compatibility.
Blazer S10/Jimmy S15 (98) – RH front engine compartment, w/o build date opt ZN4; ID 9355699
Bravada (98) – 4.3L, w/o build date opt ZN4; ID 9355699
Chevrolet/GMC Pickup 1500/2500/3500 (98-99) – Gasoline, LH front engine compartment, ID 9355699
Escalade (99) – LH front engine compartment, ID 9355699
Envoy (98) – RH front engine compartment, w/o build date opt ZN4; ID 9355699
Express/Savana Van 1500/2500/3500 (98-99) – Gasoline, ID 9355699
Isuzu Hombre (98) – 4.3L, w/o extended build date opt ZN4; ID 9355699
S10/S15/Sonoma (98) – 4.3L, w/o build date opt ZN4; ID 9355699
Safari Van (98) – LH front by battery, ID 9355699
Suburban 1500/2500 (98-99) – Gasoline, LH front engine compartment, ID 9355699
Tahoe/Yukon (98-99) – Gasoline, LH engine compartment, ID 9355699
Do I need to do anything after I install this PCM?
Do I need to do anything after I install this PCM?
Yes. While the module arrives programmed for your engine and transmission, you must perform a security relearn procedure (often called a VATS or Passlock relearn) after installation. This syncs the PCM to your vehicle’s anti-theft system. It’s a simple process that takes about 30 minutes and does not require special tools.
Why do you need my VIN?
Your Vehicle Identification Number (VIN) is essential. It allows us to access the correct GM factory software for your specific vehicle, including engine size, transmission type, and any other unique options. Programming the PCM with your VIN ensures it works perfectly right out of the box.
Is this a new part?
No, this is a high-quality, tested used OEM (Original Equipment Manufacturer) part recovered from a salvaged vehicle. We find that tested original parts are often more reliable than some aftermarket alternatives. It has been cleaned, inspected, and is ready for service.
How do I find my PCM’s part number?
Your PCM’s part number or service ID is printed on a sticker on the module itself. For most of these GM trucks and vans, you’ll find the PCM in the engine bay. The most important number to match is the service ID, which should be 9355699 for this replacement part.