Is Your 1999 Escalade or GM Truck Running Erratically?
If you’re dealing with a frustrating no-start condition, a persistent check engine light, or harsh, unpredictable shifting, the culprit is often the Powertrain Control Module (PCM). As a mechanic with over two decades of experience under the hood of these exact GM trucks and SUVs, I’ve seen firsthand how a failing PCM can cause a cascade of confusing issues. It’s the brain of your vehicle’s operation, and when it starts to fail, it can feel like the vehicle has a mind of its own. You’re not just buying a part; you’re buying a solution to get your trusted truck or SUV back to the reliable workhorse it was meant to be.
The Right Fix: A Pre-Programmed 1999 Escalade PCM
This isn’t just a used computer pulled from a shelf. This is a fully tested, genuine GM PCM that we program specifically for your vehicle using your VIN. This critical step ensures that the module has the correct software and calibrations for your Escalade’s engine, transmission, and options. We flash it with the latest updates from GM, which often resolve factory bugs and improve performance and drivability. This eliminates the need for an expensive trip to the dealership for programming.
Expert Pro Tip from a 20-Year Veteran
“A customer’s ’98 Tahoe came in last week with a no-communication code and a no-start. Everyone assumed the PCM was fried. Before swapping it, I did my standard check: I inspected the PCM’s large electrical connectors. Sure enough, the blue connector had a faint green tinge of corrosion on two pins from moisture intrusion over the years. A careful cleaning with electrical contact cleaner and a small brush restored the connection and fixed the problem entirely. Always inspect and clean your harness connectors before installing the new moduleโit’s a 5-minute check that can save you a headache.”
Common Symptoms of a Failing PCM:
- โ Check Engine Light is on with communication-related fault codes (U-codes).
- โ Engine cranks but refuses to start.
- โ Unexplained stalling, especially when warm.
- โ Harsh or delayed transmission shifting.
- โ A noticeable drop in fuel economy.
- โ Failure to pass an emissions test.
Plug-and-Play Installation: No Dealer Visit Required
Installing your replacement module is a straightforward process you can do in your own driveway. While simple, it’s important to follow the steps carefully. After installation, you will need to perform the VATS/Passlock security relearn procedure, which is a simple process that pairs the new computer to your vehicle’s anti-theft system. This procedure can be found online and typically involves turning the key on and off in a specific sequence.
- Safety First: Disconnect the negative terminal from your vehicle’s battery.
- Locate the PCM: On most compatible trucks and SUVs like the 1999 Escalade, the PCM is located in the engine bay on the driver’s side, near the firewall or inner fender.
- Disconnect Wiring: Carefully unclip and remove the wiring harness connectors. Inspect them for any damage or corrosion as mentioned in the tip above.
- Remove the Old Unit: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the Replacement: Mount your new, pre-programmed PCM, securely reconnect the wiring harnesses, and re-bolt it into place.
- Reconnect Battery: Reattach the negative battery terminal.
- Perform Security Relearn: Follow the vehicle-specific security relearn procedure to sync the module with your keys. Your truck will not start until this is completed.
Guaranteed Compatibility
This module is a direct replacement for a wide range of GM vehicles and is guaranteed to function correctly if your original module carries any of the following part numbers:
Part Numbers: 09355699, 16266645, 9355699, 16250279, 16258815, 09366810, 9366810
After purchase, simply send us your vehicle’s 17-digit VIN, and we’ll handle the programming. We’ll have your reliable, VIN-matched PCM on its way to you, ready to solve your vehicle’s issues.