Restore Peak Performance to Your GM Truck or SUV
Is your 1999 Cadillac Escalade, GMC Sierra, or Chevy Tahoe running rough, shifting erratically, or refusing to start? The Powertrain Control Module (PCM), often called the Electronic Control Module (ECM), is the central computer responsible for managing your vehicle’s engine and transmission. When it fails, it can cause a cascade of frustrating and difficult-to-diagnose issues. This replacement PCM, part number 09355699, is the definitive solution to get your vehicle back on the road, operating as it should.
This isn’t just a generic, off-the-shelf part. We take your vehicle’s specific Vehicle Identification Number (VIN) and program the module with the latest, most stable software updates directly from GM. This critical step ensures that the PCM communicates flawlessly with all other modules in your vehicle, correcting factory bugs and optimizing performance for fuel efficiency, emissions, and drivability. The result is a true plug-and-play solution that eliminates the need for an expensive trip to the dealership for programming.
From the Diagnostic Bay
We had a 1999 GMC Yukon in the shop that was driving the owner crazy. It had an intermittent no-start condition and would occasionally stall at stoplights. The check engine light was on with a handful of seemingly unrelated codes. The owner had already replaced the fuel pump and ignition coil with no success. After hooking up our diagnostic scanner and monitoring live data, we noticed erratic sensor readings that didn’t make sense. This pointed us directly to the PCM. The internal processors were failing, corrupting the data signals. We installed a VIN-programmed module just like this one, and the Yukon fired right up and ran perfectly. It’s a classic example of how a failing PCM can mimic other component failures, making a direct-fit, programmed module the fastest and most reliable fix.
Symptoms of a Failing Powertrain Control Module
- ✔ Check Engine Light is illuminated, often with communication-related error codes (U-codes).
- ✔ Engine cranks but fails to start, or experiences intermittent starting problems.
- ✔ Poor engine performance, including misfires, hesitation, or stalling.
- ✔ Noticeable decrease in fuel economy.
- ✔ Harsh or erratic automatic transmission shifting.
- ✔ Failure to pass state emissions testing.
- ✔ Inconsistent or non-functional dashboard gauges.
Why a VIN-Programmed 1999 Escalade PCM is Essential
The PCM in your late-90s GM vehicle is more than just a simple computer; it’s the heart of its electronic nervous system. It contains specific information about your vehicle’s engine size, transmission type, gear ratios, tire size, and factory options. Using a non-programmed module from a junkyard or another vehicle will almost certainly result in a no-start condition or severe operational problems. Our professional programming service uses your VIN to load the exact factory calibration file your vehicle needs. We also install the latest GM software updates, which can resolve common drivability issues that were present even when the vehicle was new. This ensures a seamless installation and restores the vehicle’s original operating parameters.
Simple Installation Process
Replacing the PCM is a straightforward job for a DIY mechanic. On most compatible models like the 1999 Escalade, Yukon, and pickups, the module is located in the engine bay on the driver’s side.
- Disconnect the Battery: Always disconnect the negative battery terminal before working on any electronic components.
- Locate the PCM: Find the module, typically a silver metal box with several large electrical connectors.
- Disconnect Connectors: Carefully unplug the wiring harnesses. There are often levers or clips that need to be released.
- Remove the Old Module: Unbolt the PCM from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed PCM into place, reconnect the wiring harnesses securely, and then reconnect the negative battery terminal.
- Perform Security Relearn (if necessary): In some cases, a simple security relearn procedure may be required. This can typically be done without special tools by cycling the ignition key and is detailed in many online forums and repair guides for these vehicles.
This module is a direct replacement for part numbers 16250279, 09366810, and 09355699, ensuring broad compatibility across a wide range of popular GM trucks, vans, and SUVs from 1998 and 1999. Verify your vehicle in the fitment list to confirm compatibility.
Frequently Asked Questions
Do I need to send you my old PCM?
No, there is no core charge or need to send us your old module. This is a direct purchase of a replacement PCM that is programmed and ready for installation.
How do I provide my VIN?
After completing your purchase, you will receive instructions on how to send us your vehicle’s 17-digit VIN. We cannot ship your order until we receive and validate your VIN, as the programming is specific to your vehicle.
Is this PCM truly plug-and-play?
Yes, for over 95% of vehicles, it is. We program it with your VIN and the latest GM software. In some rare cases, your vehicle may require a security relearn procedure, which is a simple process you can do yourself by cycling the key in the ignition.
What if my original part number is 16250279?
This module is a fully compatible replacement for part numbers 16250279, 09366810, and 09355699. As long as your vehicle is on the compatibility list, this part will function correctly.
What kind of warranty is included?
This part comes with a standard warranty against defects in materials and workmanship. Please refer to our warranty policy page for complete details and duration.