Restore Your Truck’s Performance with a VIN-Programmed PCM
Is your 1998 Chevy Blazer or GMC Jimmy acting up? Unexplained stalling, a persistent check engine light, or rough running can often be traced back to a failing Powertrain Control Module (PCM). As a technician with over two decades of experience, I’ve seen how a faulty PCM can cause a cascade of frustrating issues. This isn’t just a part; it’s the central computer for your engine and transmission. Replacing it correctly is critical, and that’s where we come in. We offer a reliable, tested OEM PCM that is professionally programmed with the latest GM software specifically for your vehicle’s VIN. This eliminates the guesswork and the need for an expensive trip to the dealership for programming.
Case Study: A Tricky Diagnosis
I remember a 1998 GMC Jimmy S15 that came into my shop with a bizarre set of symptoms. The owner complained of intermittent stalling at stoplights and a transmission that wouldn’t shift out of second gear. He’d already replaced the throttle position sensor and the vehicle speed sensor with no luck. The scanner was showing a loss of communication code (U-series) alongside a PCM processor fault (P0601). After checking the wiring harness and grounds—which looked fine—we suspected the PCM itself. The internal circuits were failing under heat soak. We swapped in a VIN-programmed module just like this one, performed the security relearn, and the truck ran perfectly. It’s a classic example of how a failing 1998 Blazer S10 PCM can mimic other component failures.
Is Your Truck Showing These Symptoms?
A failing PCM can manifest in many ways. If you’re experiencing any of the following, it might be time for a replacement:
- ✔ Check Engine Light is on with codes like P0601, P0604, or P0606
- ✔ Vehicle won’t start or is very difficult to start
- ✔ Poor or erratic engine performance and hesitation
- ✔ Decreased fuel economy for no apparent reason
- ✔ Transmission shifting problems or getting stuck in gear
- ✔ Communication errors with your scan tool
A Straightforward Guide to Installation
Installing your programmed 1998 Blazer S10 PCM is a manageable job for a confident DIYer. The key is taking your time and following the proper procedure.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On the 1998 Blazer/Jimmy, the PCM is typically located in the engine compartment on the passenger (RH) side, near the firewall or inner fender.
- Disconnect the Connectors: Carefully unlatch and remove the electrical harness connectors from the old PCM. Inspect them for any corrosion or damaged pins.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket. Keep the hardware as you may need to reuse it.
- Install the New PCM: Mount your new, pre-programmed PCM securely onto the bracket.
- Reconnect Everything: Firmly plug the harness connectors into the new module until they click and lock into place. Reconnect the negative battery terminal.
- Perform Security Relearn: You will likely need to perform a security relearn procedure (often called Passlock or VATS relearn) to allow the vehicle to start. This procedure typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’, and repeating two more times. Check your specific model’s procedure for exact details.
By purchasing this module, you are getting a cost-effective and reliable solution. We take a quality, used OEM computer and flash it to your exact VIN, ensuring it works seamlessly with your vehicle’s specific options and systems. This is the most efficient way to get your truck running right again without the high cost of a new part and dealer labor for programming.
Will This Fit My Truck or Van?
This PCM, identified by part number 16266645 or service ID 9355699, is compatible with a wide range of 1998-1999 GM vehicles. Please verify your part number or service ID before ordering. This module fits the following applications:
– ASTRO 98 (LH front by battery)
– BLAZER S10/JIMMY S15 98 (RH front engine compartment)
– BRAVADA 98 (4.3L)
– CHEVROLET 1500/2500/3500 PICKUP 98-99 (Gasoline)
– ENVOY 98 (RH front engine compartment)
– ESCALADE 99 (LH front engine compartment)
– EXPRESS 1500/2500/3500 VAN 98-99 (Gasoline)
– GMC 1500/2500/3500 PICKUP 98-99 (Gasoline)
– ISUZU HOMBRE 98 (4.3L)
– S10/S15/SONOMA 98 (4.3L)
– SAFARI (GMC) 98 (LH front by battery)
– SAVANA 1500/2500/3500 VAN 98-99 (Gasoline)
– SUBURBAN 1500/2500 98-99 (Gasoline)
– TAHOE 98-99 (Gasoline)
– YUKON 98-99 (Gasoline)
Frequently Asked Questions
How do I provide my VIN?
After you complete your purchase, simply send us a message with your 17-digit Vehicle Identification Number (VIN). We cannot program and ship the module without it.
Is this a new part?
No, this is a high-quality, tested computer that has been sourced from a salvaged vehicle. We inspect and program it to ensure full functionality, offering a reliable fix at a great value.
Will I need to do anything else after installation?
Yes. After installing the 1998 Blazer S10 PCM, you must perform the vehicle’s security relearn procedure. This syncs the new module to your anti-theft system and allows the engine to start and run. This procedure does not require any special tools.
What if my part number is slightly different?
This module is a direct replacement for several part numbers, including 09355699, 16250279, 16258815, and 9366810. As long as your vehicle is on the compatibility list and your original module has service ID 9355699, this part will work correctly once programmed to your VIN.
What happens if I don’t do the security relearn?
If the security relearn is not performed, your vehicle’s anti-theft system will activate. This will typically result in a crank/no-start condition, where the engine turns over but will not fire up and run.