Restore Peak Performance to Your GM Truck or Van
If you’re dealing with frustrating, hard-to-diagnose issues on your 1998 GMC Safari or another compatible GM vehicle, the Powertrain Control Module (PCM) is often the culprit. As a technician with over two decades of experience, I’ve seen firsthand how a failing PCM can create a cascade of problems that mimic other component failures, leading to wasted time and money on parts you don’t need. This isn’t just a replacement part; it’s a direct solution to get your reliable GM vehicle back on the road, running as it should.
This is a thoroughly tested, used OEM PCM that we program specifically to your vehicle’s VIN before it ships. This critical step ensures all factory settings and the latest GM software updates are loaded, making the installation process as seamless as possible. You get the reliability of an original part without the steep cost and programming hassle of a dealership visit. By providing us with your VIN at checkout, you’re getting a module that is truly tailored for your truck or van’s specific configuration.
Case Study: The Ghost in the Machine
A 1999 Chevy Suburban came into my bay with an issue that had stumped two other shops. The owner reported random stalling at stoplights and occasional harsh shifting. They had already replaced the fuel pump and a throttle position sensor to no avail. A scan showed no hard fault codes, just a history of intermittent communication loss (U-codes). Experience pointed me toward the PCM. Heat soak was likely causing an internal connection to fail. We installed a VIN-programmed PCM just like this one, and the ghost was gone. The truck ran perfectly, proving that a solid, correctly programmed 1998 GMC Safari PCM or its equivalent is the foundation of a healthy vehicle.
Is Your GM Truck or Van Showing These Signs?
A faulty engine computer can manifest in numerous ways. If you’re experiencing any of the following, a failing PCM could be the root cause:
- ✔ Check Engine Light is on with internal module codes like P0601, P0602, or P0606.
- ✔ The engine cranks but refuses to start.
- ✔ Unexplained drops in fuel economy.
- ✔ The transmission shifts erratically, harshly, or gets stuck in one gear (limp mode).
- ✔ Your scan tool cannot communicate with the PCM.
- ✔ Stalling, sputtering, or rough idling for no apparent reason.
- ✔ Apparent failure of multiple sensors at once.
A Straightforward Guide to Your PCM Swap
Installing your programmed 1998 GMC Safari PCM is a job most DIYers can handle with basic tools. Follow these steps to ensure a smooth process:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental reconnection.
- Locate the Module: On most of these GM trucks and vans, the PCM is located in the engine compartment, often on the driver’s side near the battery or on the fender wall. Refer to your vehicle’s service manual for the exact position.
- Disconnect and Remove: Carefully unplug the electrical connectors. These usually have locking tabs that need to be released. Once disconnected, unbolt the module from its mounting bracket and remove it.
- Install the New PCM: Mount the new, programmed PCM in the same location and securely fasten it. Reconnect the electrical harnesses, making sure they click firmly into place.
- Reconnect Power: Reattach the negative battery terminal.
- Perform Security Relearn (If Necessary): Some GM vehicles with Passlock/Passkey security systems may require a simple relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating two more times before starting the engine. This allows the new PCM to sync with your vehicle’s anti-theft system.
Verified Vehicle Compatibility List
This module, identified by service number 09355699, is a direct replacement for a wide range of GM vehicles. Please verify your part number and match it to the list below. This part is compatible with part numbers 16250279, 16266645, 9355699, 16258815, 09366810, and 9366810.
BLAZER S10/JIMMY S15 98 Electronic Control Module; (RH front engine compartment), w/o build date opt ZN4; ID 9355699
BRAVADA 98 Electronic Control Module; (6-262, 4.3L), w/o build date opt ZN4; ID 9355699
CHEVROLET 1500 PICKUP 98-99 Electronic Control Module; gasoline (LH front engine compartment), ID 9355699
CHEVROLET 2500 PICKUP 98-99 Electronic Control Module; gasoline (LH front engine compartment), ID 9355699
CHEVROLET 3500 PICKUP 98-99 Electronic Control Module; gasoline (LH front engine compartment), ID 9355699
ENVOY 98 Electronic Control Module; (RH front engine compartment), w/o build date opt ZN4; ID 9355699
ESCALADE 99 Electronic Control Module; (LH front engine compartment), ID 9355699
EXPRESS 1500 VAN 98-99 Electronic Control Module; ID 9355699
EXPRESS 2500 VAN 98-99 Electronic Control Module; gasoline, ID 9355699
EXPRESS 3500 VAN 98-99 Electronic Control Module; gasoline, ID 9355699
GMC 1500 PICKUP 98-99 Electronic Control Module; gasoline (LH engine compartment), ID 9355699
GMC 2500 PICKUP 98-99 Electronic Control Module; gasoline (LH engine compartment), ID 9355699
GMC 3500 PICKUP 98-99 Electronic Control Module; gasoline (LH engine compartment), ID 9355699
ISUZU HOMBRE 98 Electronic Control Module; 4.3L (6 cylinder), w/o extended build date opt ZN4; ID 9355699
S10/S15/SONOMA 98 Electronic Control Module; 6-262 (4.3L), w/o build date opt ZN4; ID 9355699
SAFARI (GMC) 98 Electronic Control Module; (LH front by battery), ID 9355699
SAVANA 1500 VAN 98-99 Electronic Control Module; ID 9355699
SAVANA 2500 VAN 98-99 Electronic Control Module; gasoline, ID 9355699
SAVANA 3500 VAN 98-99 Electronic Control Module; gasoline, ID 9355699
SUBURBAN 1500 98-99 Electronic Control Module; gasoline (LH front engine compartment), ID 9355699
SUBURBAN 2500 98-99 Electronic Control Module; gasoline (LH front engine compartment), ID 9355699
TAHOE 98-99 Electronic Control Module; gasoline (LH front engine compartment), ID 9355699
YUKON 98-99 Electronic Control Module; (LH engine compartment), ID 9355699
Frequently Asked Questions
What do I need to do after purchasing?
After you complete your purchase, you must provide us with your vehicle’s 17-digit VIN. We cannot program or ship your module without it. This ensures the 1998 GMC Safari PCM is perfectly matched to your vehicle’s factory specifications.
Is this part difficult to install?
No, this is a direct-fit replacement. Because we program it beforehand, it’s designed to be a plug-and-play solution. In some cases, a simple security relearn procedure may be required, which does not need special tools.
What is the difference between a PCM and an ECM?
ECM stands for Engine Control Module and PCM stands for Powertrain Control Module. For these GM vehicles, the terms are often used interchangeably as the module controls both the engine and transmission functions. This part serves as the central powertrain computer.
Why should I choose a used OEM part?
A used Original Equipment Manufacturer (OEM) part offers the best of both worlds: the proven reliability and perfect fitment of a factory component at a fraction of the cost of a new one from a dealer. Each unit is tested to ensure functionality.
Where is this module located on my vehicle?
On most compatible models like the Safari, Astro, and full-size trucks/vans, the PCM is found in the engine bay, typically on the driver’s side fender well or near the battery. On S10/Blazer/Jimmy models, it may be on the passenger side.