Restore Peak Performance to Your GM Truck or SUV
Is your trusty Chevrolet Blazer, GMC Jimmy, or S10 pickup suddenly giving you headaches? Unexplained stalling, a persistent Check Engine Light, rough idling, or a frustrating no-start condition can often point directly to a failing Powertrain Control Module (PCM). As the central computer of your vehicle, the PCM manages everything from fuel mixture and ignition timing to transmission shift points. When it falters, the symptoms can be unpredictable and difficult to diagnose. This is the reliable, straightforward solution you need to get your vehicle back on the road with confidence.
We offer a professionally prepared PCM, part number 16265035, that arrives at your door ready for installation. The key to our service is the VIN-specific programming. Before we ship, we flash the module with the latest official GM software calibration that matches your vehicle’s exact Vehicle Identification Number (VIN). This critical step ensures seamless communication with your truck’s other systems, eliminates the need for an expensive trip to the dealership for programming, and often corrects drivability issues present in the original factory software. This is the definitive fix for a faulty 1998-2000 Blazer S10 PCM.
A Technician’s Notebook: The ’99 Jimmy That Wouldn’t Start
I remember a 1999 GMC Jimmy getting towed into the shop. The owner said it died at a stoplight and wouldn’t crank over again. All the lights worked, the battery was new, but it was completely dead otherwise. He’d already replaced the starter and ignition switch. After checking the basics—fuses, relays, and grounds—my scan tool couldn’t communicate with the engine computer at all. That’s a classic red flag. On these S-platform trucks, the PCM is located in the engine bay, where it’s exposed to heat and vibration. Over 20+ years, internal circuit board connections can fail. We confirmed the PCM had power and ground but wasn’t communicating. A replacement, pre-programmed 1998-2000 Blazer S10 PCM like this one was the answer. Once installed, the truck fired right up, and the scan tool connected instantly. It was a 30-minute fix that solved a week-long headache for the customer.
Is Your Truck Showing These Symptoms?
A failing PCM can cause a wide range of issues. If you’re experiencing any of the following, a faulty engine computer could be the culprit:
- âś” Check Engine Light is on with codes like P0601, P0604, or P0606 (Internal Module Failure)
- âś” Vehicle will not start or is very hard to start
- âś” Engine stalls randomly while driving or at idle
- âś” Noticeable decrease in fuel economy
- âś” Harsh or erratic automatic transmission shifting
- âś” Failure to pass an emissions/smog test
- âś” Loss of communication with the scan tool
A Straightforward Guide to Your PCM Swap
Installing your new PCM is a job most DIYers can handle in their driveway with basic hand tools. Follow these steps for a smooth installation:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery and secure it away from the post to prevent any accidental power surges.
- Locate the PCM: On most S10/Blazer/Jimmy models, the PCM is located in the engine compartment on the right-hand (passenger) side, near the firewall or inner fender. For vans and full-size trucks, it may be on the driver’s side. Refer to your vehicle’s service manual for the exact location.
- Disconnect the Connectors: Carefully unclip and remove the electrical wiring harness connectors from the old PCM. These connectors have locking tabs that need to be released before they can be pulled off. Avoid forcing them.
- 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 Module: Mount your new, pre-programmed PCM onto the bracket and secure it with the bolts.
- Reconnect Everything: Firmly plug the wiring harness connectors into the new PCM until they click into place. Reconnect your vehicle’s negative battery terminal.
- Final Step: In some cases, a security relearn procedure may be necessary. This typically involves turning the key to the ‘ON’ position for 10-15 minutes. Your vehicle is now ready to start.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 16263494, 16265035, 8162634940, 218-11787, and 21811787. It is guaranteed to fit a wide range of GM vehicles. Please verify your part number and check the list below. This is not a complete list, so if you have questions, please contact us with your VIN.
CHEVROLET 2500 PICKUP 00 Electronic Control Module; gasoline (LH front engine compartment)
EXPRESS 1500 VAN 00 Electronic Control Module; (LH rear engine compartment)
EXPRESS 2500 VAN 00 Electronic Control Module; (LH rear engine compartment), gasoline
EXPRESS 3500 VAN 00 Electronic Control Module; (LH rear engine compartment), gasoline
SAVANA 1500 VAN 01-02 Electronic Control Module; (LH rear engine compartment), ID 16263494
ASTRO 00-01 Electronic Control Module; (LH front by battery), ID 16263494
GMC 3500 PICKUP 00 Electronic Control Module; gasoline (LH front engine compartment)
EXPRESS 2500 VAN 01-02 Electronic Control Module; (LH rear engine compartment), gasoline, ID 16263494
S10/S15/SONOMA 99-00 Electronic Control Module; (RH front engine compartment), 4.3L
SAVANA 1500 VAN 00 Electronic Control Module; (LH rear engine compartment)
ASTRO 99 Electronic Control Module; (LH front by battery), (4.3L), ID 16263494
ISUZU HOMBRE 99-00 Electronic Control Module; (RH front engine compartment), 4.3L (6 cylinder)
SAFARI (GMC) 99-01 Electronic Control Module; (LH front by battery), ID 16263494
SAVANA 3500 VAN 01-02 Electronic Control Module; (LH rear engine compartment), gasoline, ID 16263494
EXPRESS 1500 VAN 99 Electronic Control Module; (LH rear engine compartment), ID 16263494
GMC 1500 PICKUP 99 Electronic Control Module; 5.0L, (LH engine compartment), ID 16263494
BLAZER S10/JIMMY S15 98 Electronic Control Module; (RH front engine compartment), w/build date opt ZN4
GMC 1500 PICKUP 99 Electronic Control Module; 5.7L, (LH engine compartment), ID 16263494
SAVANA 3500 VAN 99 Electronic Control Module; (LH rear engine compartment), gasoline, ID 16263494
TAHOE 00 Electronic Control Module; Classic style (LH front engine compartment)
YUKON 99 Electronic Control Module; (LH engine compartment), ID 16263494
ESCALADE 99 Electronic Control Module; (LH front engine compartment), ID 16263494
ESCALADE 00 Electronic Control Module; (LH front under battery)
S10/S15/SONOMA 98 Electronic Control Module; 6-262 (4.3L), w/build date opt ZN4
YUKON 00 Electronic Control Module; (LH front under battery), Denali
BRAVADA 98 Electronic Control Module; (6-262, 4.3L), w/build date opt ZN4
BLAZER S10/JIMMY S15 99-00 Electronic Control Module; (RH front engine compartment)
Frequently Asked Questions
Do I need to do anything else after installing this PCM?
Do I need to do anything else after installing this PCM?
Because this module comes pre-programmed to your VIN, it is typically a plug-and-play installation. In some cases, a simple security relearn procedure (often just leaving the key in the ‘ON’ position for 10-15 minutes) is required for the vehicle to start. No special scan tools are needed.
What is a VIN and why do you need it?
Do I need to do anything else after installing this PCM?
Because this module comes pre-programmed to your VIN, it is typically a plug-and-play installation. In some cases, a simple security relearn procedure (often just leaving the key in the ‘ON’ position for 10-15 minutes) is required for the vehicle to start. No special scan tools are needed.
Where is the PCM located on my 1999 S10?
Do I need to do anything else after installing this PCM?
Because this module comes pre-programmed to your VIN, it is typically a plug-and-play installation. In some cases, a simple security relearn procedure (often just leaving the key in the ‘ON’ position for 10-15 minutes) is required for the vehicle to start. No special scan tools are needed.
Will a new PCM fix my transmission shifting problems?
Do I need to do anything else after installing this PCM?
Because this module comes pre-programmed to your VIN, it is typically a plug-and-play installation. In some cases, a simple security relearn procedure (often just leaving the key in the ‘ON’ position for 10-15 minutes) is required for the vehicle to start. No special scan tools are needed.
Is this a new or used part?
Do I need to do anything else after installing this PCM?
Because this module comes pre-programmed to your VIN, it is typically a plug-and-play installation. In some cases, a simple security relearn procedure (often just leaving the key in the ‘ON’ position for 10-15 minutes) is required for the vehicle to start. No special scan tools are needed.