Is Your Late-90s GM Truck or Van Acting Up?
If you’re dealing with a persistent check engine light, erratic transmission shifting, a frustrating no-start condition, or bizarre electrical gremlins on your 1998-1999 GM vehicle, the problem often points directly to a failing Powertrain Control Module (PCM). As a technician with over two decades of experience under the hood, I’ve seen countless owners replace perfectly good sensors and parts, only to find the root cause was the vehicle’s computer all along. This isn’t just a part; it’s the brain of your engine and transmission, and when it fails, it can cause chaos.
This is your direct, reliable solution. We are offering a genuine, used GM PCM with service number 9355699. Before we ship it, our experts will program it with the latest GM software updates specifically matched to your vehicle’s 17-digit VIN. This means it arrives at your door ready for a straightforward installation, saving you a costly trip to the dealership and the hassle of finding a shop with the right programming equipment.
The Right Fix for Your 1998-1999 Chevrolet 1500 PCM
Don’t let a faulty computer keep your reliable truck off the road. A failing PCM can manifest in ways that are easily misdiagnosed. I recall a customer’s ’99 Suburban that came into my shop with what he thought was a bad transmission. It was shifting hard and randomly dropping out of overdrive. After checking the basics, we found the PCM was sending erratic signals to the transmission solenoids. Swapping in a correctly programmed PCM like this one solved the problem instantly, saving him from a thousand-dollar transmission rebuild. This module is the key to restoring factory performance and reliability.
- ✔ VIN-Programmed for You: We flash this module with your vehicle’s specific VIN, ensuring perfect communication and function.
- ✔ Latest GM Software: Your PCM will be loaded with the most current calibrations available from General Motors for improved performance and efficiency.
- ✔ Cost-Effective Solution: Get a dependable, tested part without the high price tag of a new-from-dealer module.
- ✔ Solves Common Issues: Corrects problems like false sensor codes, harsh shifting, poor fuel economy, and no-start conditions related to the PCM.
- ✔ Broad Compatibility: This unit is a direct replacement for multiple part numbers, including 16266645, 16250279, 16258815, and 09366810.
Simple Installation to Get You Running Again
You don’t need to be a master mechanic to replace this module. With basic hand tools, you can get your vehicle back in order. Follow these simple steps:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most trucks and SUVs like the Chevrolet 1500, Tahoe, and Suburban, the PCM is located in the engine compartment on the driver’s side, often near the fender or firewall. On vans like the Express and Savana, it’s typically in the LH rear of the engine compartment.
- Disconnect and Remove: Carefully unclip and remove the electrical connectors. Be gentle, as the plastic can be brittle on older vehicles. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the replacement PCM into place and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock in.
- Reconnect Battery: Re-attach the negative battery terminal. In many cases, the vehicle will start and run perfectly. Some models may require a simple security relearn procedure, which can be done without special tools (instructions are widely available online).
Expert Pro Tip From a 20-Year Veteran
Before you plug in your replacement PCM, take a close look at the pins inside your vehicle’s wiring harness connectors. Over the years, moisture and dirt can cause a green, powdery corrosion to form on the pins. This creates poor contact and can cause intermittent issues that you might mistake for another faulty part. Use a small amount of electrical contact cleaner and a soft brush (an old toothbrush works well) to gently clean the pins and ensure a solid, reliable connection.
Guaranteed Fitment for Your Vehicle
This Electronic Control Module is guaranteed to fit a wide range of 1998 and 1999 General Motors vehicles that require service number 9355699. This includes, but is not limited to, the Chevrolet & GMC 1500/2500/3500 Pickups, Suburban, Tahoe, Yukon, Escalade, Express/Savana Vans, S10/Sonoma, Blazer/Jimmy, and more. Please verify the number on your original module to ensure a perfect match.