Restore Peak Performance to Your GM Truck or SUV
Is your trusty 1999 Cadillac Escalade, Suburban, or Tahoe suddenly running rough, stalling, or refusing to start? As a technician with over 20 years of experience, I’ve seen these symptoms countless times. More often than not, the culprit is a failing Powertrain Control Module (PCM), the electronic brain of your vehicle. When it falters, it can cause a cascade of frustrating and hard-to-diagnose issues. This isn’t just an inconvenience; it’s a reliability problem that can leave you stranded.
We offer a dependable and straightforward solution: a genuine, used OEM engine computer that has been meticulously tested and is ready for installation. The best part? We handle the complex part for you. This module is not just a part in a box; it’s a complete service. We will flash the unit with the latest GM software updates and program it specifically to your vehicle’s Vehicle Identification Number (VIN) before it ever leaves our facility. This means you get a part that is truly plug-and-drive, eliminating the need for an expensive trip to the dealership for programming.
Case Study: A Tricky Diagnosis
A few months back, a 1999 GMC Yukon came into the shop on a tow truck. The owner had replaced the fuel pump, spark plugs, and ignition coil, but it still had an intermittent no-start condition. No specific codes were stored, just a general feeling that the engine wasn’t getting the right commands. After checking all the basics, we hooked up a scope to the injector pulse signals and saw they were erratic. We swapped in one of our pre-programmed PCMs, and the truck fired up instantly and ran perfectly. The original PCM had an internal fault that only showed up under certain conditions—a classic failure mode for these units. This replacement 1999 Escalade PCM is the exact solution for that kind of problem.
Is Your GM Truck Showing These Symptoms?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, this module is likely the solution you need. In my shop, these are the tell-tale signs that point directly to the engine computer.
- âś” Check Engine Light is illuminated with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0605 (Internal Control Module Read Only Memory (ROM) Error).
- âś” The engine cranks but refuses to start.
- âś” Unexplained stalling, especially after the engine has warmed up.
- âś” Noticeably poor fuel economy and sluggish performance.
- âś” Harsh or erratic automatic transmission shifting.
- âś” Communication errors with your scan tool.
A Straightforward Guide to Installation
Replacing the PCM on these GM vehicles is a job most DIYers can handle in under 30 minutes with basic hand tools. Our pre-programming makes it even simpler. While this 1999 Escalade PCM is plug-and-play, you may need to perform a simple security relearn procedure after installation, which does not require any special tools.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- 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 Harnesses: Carefully unclip and remove the electrical 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 Module: Bolt your new, pre-programmed PCM into the mounting bracket.
- Reconnect Everything: Firmly plug the electrical harnesses back into the new PCM and reconnect the negative battery terminal.
- Perform Security Relearn (If Needed): Turn the key to the ‘ON’ position for 10-15 minutes, then off for 10 seconds. Repeat this cycle three times. On the fourth try, the vehicle should start and run normally.
Verified Vehicle Compatibility
This engine computer, identified by service number 16250279 or ID 09355699, is a guaranteed fit for a wide range of GM vehicles. Please match your part number or vehicle from the list below to ensure compatibility. This unit replaces part numbers: 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, and 9366810.
CHEVROLET/GMC 1500/2500/3500 PICKUP 98-99 (Gasoline)
CHEVROLET/GMC SUBURBAN 1500/2500 98-99 (Gasoline)
CHEVROLET TAHOE / GMC YUKON 98-99 (Gasoline)
CHEVROLET EXPRESS / GMC SAVANA VAN 1500/2500/3500 98-99 (Gasoline)
CHEVROLET ASTRO / GMC SAFARI 98
OLDSMOBILE BRAVADA 98
GMC ENVOY 98
CHEVROLET S10 / GMC SONOMA 98 (4.3L)
CHEVROLET BLAZER / GMC JIMMY 98 (4.3L)
ISUZU HOMBRE 98 (4.3L)
Note: Please verify the ID number 9355699 on your original module.
Frequently Asked Questions
Do I need to do anything after I buy it?
Yes. After your purchase, you MUST provide us with your 17-digit VIN. We cannot program and ship your module without it. This ensures the PCM is a perfect match for your vehicle’s specific configuration.
Is this a new part?
No, this is a high-quality, tested used OEM part sourced from a salvaged vehicle. This provides OEM reliability at a fraction of the cost of a new unit from a dealer.
Will I need to have this programmed by a dealer?
Absolutely not! The main benefit of our service is that we program the module for you. It will arrive ready to install, saving you time and hundreds of dollars in dealership programming fees.
What is the security relearn procedure?
For many GM vehicles of this era, the Passlock security system needs to sync with the new PCM. It’s a simple process that involves cycling the ignition key and waiting, as described in the installation steps. No special tools are required.
How do I find my part number?
Your vehicle’s PCM will have a sticker on it with the service number. For this application, you are likely looking for ID 09355699 or one of the compatible part numbers listed above.