Is Your GM Truck or Van Running Rough?
If your late-90s Chevrolet, GMC, or Cadillac is suffering from frustrating issues like a persistent Check Engine Light, erratic shifting, a no-start condition, or terrible fuel economy, a failing Powertrain Control Module (PCM) is often the culprit. As the central computer for your engine and transmission, its health is critical. When it fails, it can leave you stranded and chasing phantom problems. This isn’t just an inconvenience; it’s a problem that needs a reliable, straightforward solution.
The Direct Solution: A VIN-Programmed PCM
This is a dependable, used OEM Powertrain Control Module, service number 9355699, ready to get your vehicle back on the road. We take the guesswork and high cost out of the repair. Before we ship it, our technicians will professionally flash the module with the latest GM-certified software, programming it specifically to your vehicle’s 17-digit VIN. This ensures that it communicates perfectly with your truck or van’s specific systems, just like the original unit from the factory.
From the Shop Floor: A Real-World Diagnosis
“A customer’s ’99 Tahoe came in last week with an intermittent no-start and a code for the fuel pump circuit. He’d already replaced the pump and the relay with no luck. After a quick check with the scope, we found the PCM wasn’t commanding the fuel pump relay to turn on. The internal driver had failedโa classic issue I’ve seen on hundreds of these GMT400 platform vehicles. We installed one of our VIN-programmed PCMs, performed the security relearn, and it fired right up. It’s a 30-minute fix for a problem that can seem like a nightmare.”
Why Choose Our Programmed 1998-1999 Chevrolet 3500 PCM?
- โ VIN-Programmed for You: We flash the module with your vehicle’s VIN, ensuring it’s a true plug-and-play part.
- โ Latest GM Software: Your PCM arrives with the most current GM calibrations, which can resolve factory bugs and improve performance and efficiency.
- โ No Dealer Required: Save hundreds of dollars by avoiding dealership programming fees. Installation and a simple security relearn can be done in your own driveway.
- โ Cost-Effective Repair: Get a reliable, tested OEM part for a fraction of the cost of a new module.
- โ Broad Compatibility: This single part number, 9355699, is the correct service replacement for a huge range of popular GM trucks and vans.
Plug-and-Play Installation: No Dealer Visit Required
Installing your replacement PCM is a straightforward process. While specific locations vary slightly, it’s typically found in the engine bay.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On most trucks and vans like the Chevrolet 3500, Suburban, or Express, the PCM is located on the driver’s side fender or near the firewall.
- Disconnect the Old Unit: Carefully unclip and remove the electrical harness connectors. They have locking tabs that need to be released. Then, unbolt the module from its bracket.
- Install the New PCM: Bolt the replacement module into place and securely reconnect the harness connectors. Ensure they click into place.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: Your vehicle’s anti-theft system (VATS/Passlock) needs to sync with the new PCM. This typically involves turning the key to ‘ON’ for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. Your vehicle should then start.
Expert Pro Tip: Connector Inspection
Before plugging in your replacement PCM, take 60 seconds to inspect the vehicle’s harness connectors with a bright flashlight. Over 20+ years, these connectors can accumulate green corrosion or have pins that get bent or pushed back. Use a small pick and electrical contact cleaner to gently clean and straighten any problematic pins. A bad connection is the #1 cause of a replacement module not working correctly.
Guaranteed Compatibility
This module is a direct replacement for units with the service number 9355699 printed on the label. It also interchanges with the following part numbers: 09355699, 16266645, 16250279, 16258815, 09366810, and 9366810. Please verify the part number on your original module or check the fitment list to confirm this is the correct part for your vehicle. After purchase, simply send us a message with your VIN, and we’ll handle the rest.