Restore Your Truck’s Brain and Get Back to Work
Is your trusty GM truck or van suddenly unreliable? Stalling at intersections, refusing to start, or throwing a persistent Check Engine Light can bring your work to a halt. In my 20+ years of diagnostics, I’ve seen countless vehicles sidelined by a faulty Powertrain Control Module (PCM). It’s the central computer of your vehicle, and when it fails, it can cause a cascade of confusing and frustrating problems. This isn’t just an inconvenience; it’s a loss of productivity and peace of mind.
This is your direct-fit, affordable solution. We offer a genuine, used OEM PCM, part number 09355699, that has been carefully sourced and tested. The real value, especially for the DIY mechanic or independent shop, is our professional programming service. Before we ship it, we flash the module with the latest GM software updates specifically for your vehicle using your VIN. This means it arrives ready for installation, saving you a costly trip to the dealership and eliminating the need for expensive programming tools. Get your vehicle running smoothly again with a reliable part that’s programmed to perform.
From the Diagnostic Bay: The Case of the Phantom Misfire
A customer brought in a ’99 Suburban with what he described as a random, hard-to-diagnose misfire and occasional stalling. He’d already replaced plugs, wires, and the coil. Scans showed intermittent communication loss codes, but nothing consistent. After checking all the primary ignition components and verifying fuel pressure, we focused on the PCM. I’ve learned over the years that before condemning a module, you always check its power and ground circuits. We found a corroded ground wire near the engine block that was causing voltage drops to the PCM. While in his case a simple wire fix solved it, about 70% of the time with these symptoms, the internal drivers of the PCM itself are the culprit. A failing module can send you chasing ghosts all over the engine bay. This is why a properly functioning, correctly programmed 1998-1999 GMC 3500 PCM is absolutely critical.
Is Your GM Truck or Van Showing These Signs?
- âś” Check Engine Light is on with communication error codes (e.g., P0601, P0605).
- âś” The engine cranks but refuses to start.
- âś” Unexplained stalling or rough idling.
- âś” Poor fuel economy and decreased engine performance.
- âś” Harsh or erratic automatic transmission shifting.
- âś” The anti-theft or security light stays on, preventing the engine from starting.
A Straightforward Guide to Installation
Installing your programmed PCM is a manageable job for a confident DIYer. Taking your time and following these steps will ensure a smooth process. Remember, this is a general guide; your specific vehicle may have slight variations.
- 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 well or firewall.
- Disconnect the Connectors: Carefully unclip the wire harness connectors from the old PCM. These connectors have locking tabs; be gentle to avoid breaking them. There are usually multiple color-coded connectors.
- 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 PCM: Mount your new, pre-programmed PCM onto the bracket and secure it with the original bolts.
- Reconnect Everything: Firmly plug the wire harness connectors into the new module. You should hear a click as they lock into place. Reconnect the negative battery terminal.
- Security Relearn Procedure: In many cases, you will need to perform a security relearn procedure to sync the new PCM with your vehicle’s anti-theft system. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then off, and repeating this process three times. Your vehicle’s service manual will have the exact procedure.
Verified Vehicle Compatibility
This module is a direct replacement for service ID 09355699 and is also compatible with part numbers 16266645, 16250279, 16258815, and 09366810. It fits a wide range of GM vehicles. Please verify the ID on your original module to ensure a perfect match.
- Cadillac Escalade: 1999
- Chevrolet/GMC C/K 1500, 2500, 3500 Pickup (Gasoline): 1998-1999
- Chevrolet/GMC Suburban 1500, 2500 (Gasoline): 1998-1999
- Chevrolet Tahoe / GMC Yukon (Gasoline): 1998-1999
- Chevrolet Express / GMC Savana 1500, 2500, 3500 Van (Gasoline): 1998-1999
- Chevrolet Astro / GMC Safari: 1998
- Chevrolet S10 / GMC Sonoma (4.3L): 1998
- Chevrolet Blazer / GMC Jimmy (4.3L): 1998
- Oldsmobile Bravada (4.3L): 1998
- GMC Envoy (4.3L): 1998
- Isuzu Hombre (4.3L): 1998
Frequently Asked Questions
Frequently Asked Questions
Do I need to do anything after I buy it?
Yes. After your purchase, you must send us your vehicle’s 17-digit VIN (Vehicle Identification Number). We cannot program and ship the module without it. This ensures the PCM has the correct software for your truck’s specific options.