Get Your GM Truck Running Smoothly Again
As a technician with over two decades of experience under the hood, I’ve seen countless GM trucks and SUVs from the late ’90s come into the shop with baffling issues: intermittent stalling at stoplights, a stubborn no-start condition that comes and goes, or a check engine light that just won’t stay off. More often than not, the culprit is a failing Powertrain Control Module (PCM). This isn’t just a part; it’s the brain of your vehicle, and when it starts to falter, it can cause chaos. That’s why we offer this fully tested, reliable OEM 1998-1999 Yukon PCM, the definitive solution to get your truck back on the road with confidence.
What makes our service different? We take the biggest headache out of the repair process: programming. Before this module ever leaves our facility, we flash it with the latest GM software updates, specifically programmed to your vehicle’s unique VIN. This means you get a part that’s ready to install right out of the box, saving you a costly trip to the dealership and the hassle of coordinating with a technician for programming. This is the straightforward, dependable fix you’ve been looking for.
Case Study: A Tricky Diagnosis
I remember a ’99 Suburban that came in on a tow truck. The owner was frustrated; he’d already replaced the fuel pump and the ignition coil, but the truck would still randomly die and refuse to restart for hours. No consistent codes were stored, just a few random communication errors. After verifying fuel pressure and spark were indeed dropping out together, my gut pointed to the PCM. We swapped in a known-good unit, and it fired right up and ran perfectly for days. The original PCM’s internal processor was failing under heat. This pre-programmed module is the exact fix that solved his problem and has solved hundreds since.
Is Your Truck or SUV Showing These Signs of a Bad PCM?
- ✔ Sudden engine stalling or cutting out while driving.
- ✔ Intermittent no-start condition, even with a good battery and starter.
- ✔ Check Engine Light is on with codes like P0601 (Internal Control Module Memory Check Sum Error) or P0606 (ECM/PCM Processor Fault).
- ✔ Poor or erratic automatic transmission shifting.
- ✔ A noticeable drop in fuel economy for no apparent reason.
- ✔ Engine misfires or rough idling that can’t be traced to plugs, wires, or coils.
- ✔ Failure to communicate with a diagnostic scan tool.
Your Straightforward Installation Guide
- ✔ Safety First: Always disconnect the negative terminal from your vehicle’s battery and wait 10-15 minutes to allow the system to fully discharge.
- ✔ Locate the PCM: On most of these GM trucks and SUVs, the PCM is located in the engine compartment, typically on the driver’s side inner fender or near the firewall.
- ✔ Disconnect and Remove: Carefully unplug the electrical connectors. There are usually retaining clips that need to be released. Once disconnected, unbolt the module from its mounting bracket.
- ✔ Install the New Module: Bolt the new PCM into place and securely reconnect all electrical harnesses. Ensure they click into place to establish a solid connection.
- ✔ Reconnect the Battery: Reattach the negative battery terminal.
- ✔ Perform Security Relearn (CRITICAL): These vehicles require a simple security relearn procedure. Turn the key to the “ON” position (without starting) for 10-15 minutes. The “Security” light should turn off. Turn the key off for 10 seconds, then repeat the process two more times. After the third cycle, the vehicle should start and run normally.
Verified Compatibility for Your Vehicle
This module is a direct replacement for service number 9355699 and is interchangeable with part numbers 09355699, 16266645, 16250279, 16258815, and 09366810. It is guaranteed to fit the following models equipped with a gasoline engine and matching part number:
- Cadillac Escalade: 1999
- Chevrolet Astro Van: 1998
- Chevrolet Blazer S10: 1998
- Chevrolet Express 1500/2500/3500 Van: 1998-1999
- Chevrolet C/K 1500/2500/3500 Pickup: 1998-1999
- Chevrolet S10 Pickup: 1998
- Chevrolet Suburban 1500/2500: 1998-1999
- Chevrolet Tahoe: 1998-1999
- GMC Envoy: 1998
- GMC Jimmy S15: 1998
- GMC C/K 1500/2500/3500 Pickup: 1998-1999
- GMC Safari Van: 1998
- GMC Savana 1500/2500/3500 Van: 1998-1999
- GMC Sonoma S15: 1998
- GMC Yukon: 1998-1999
- Isuzu Hombre: 1998 (4.3L)
- Oldsmobile Bravada: 1998
Frequently Asked Questions
Do I need to have this PCM programmed by a dealer?
No. We handle all the programming for you before we ship the part. Just provide your vehicle’s VIN at checkout, and it will arrive ready for installation and a simple security relearn procedure.
What is a VIN and where do I find it?
The VIN (Vehicle Identification Number) is your car’s unique 17-digit serial number. You can find it on your driver’s side dashboard (visible through the windshield), on the driver’s side door jamb sticker, or on your vehicle’s registration and insurance documents.
Is this a new part?
This is a reliable, fully functional OEM part that has been sourced from a salvaged vehicle. Each unit is thoroughly inspected and tested to ensure it meets or exceeds original factory standards before being programmed and shipped.
What is the security relearn procedure?
It’s a simple process you can do yourself with just the ignition key to sync the new PCM with your vehicle’s anti-theft system. We include clear instructions, but it generally involves cycling the key to the ‘ON’ position for 10 minutes, three consecutive times.
How do I know if my original PCM is part number 9355699?
The part number is printed on a sticker on the case of your current PCM. You will need to locate and visually inspect your module to confirm the number matches 9355699 or one of the compatible cross-referenced numbers listed.
Will this fix my transmission shifting problems?
In many cases, yes. The PCM controls engine performance and transmission shift points. If the module is faulty, it can cause harsh shifting, delayed engagement, or hunting for gears. Replacing a bad PCM often resolves these related issues.