Restore Peak Performance to Your GM Truck or SUV
If you’re dealing with frustrating issues like a persistent check engine light, erratic engine behavior, poor fuel mileage, or even a no-start condition, a failing Powertrain Control Module (PCM) is often the culprit. As the central computer for your vehicle’s engine and transmission, its proper function is critical. This isn’t just a replacement part; it’s a comprehensive, ready-to-install solution for your 2003 Isuzu Ascender PCM and a wide range of other GM vehicles. We take the guesswork and hassle out of the repair by programming the module specifically for your vehicle before it ever leaves our facility.
Simply provide us with your Vehicle Identification Number (VIN) during checkout, and our technicians will flash the unit with the latest official GM software updates. This ensures perfect communication between the module and your vehicle’s systems, restoring the original performance and efficiency you’ve been missing. You get a reliable part that’s ready for a straightforward installation, saving you a costly trip to the dealership and the extra expense of programming fees.
A Technician’s Notebook
I recently worked on a 2004 Chevy Tahoe that had its owner completely stumped. The truck would crank but wouldn’t start, and it had intermittent stalling issues for weeks prior. The owner had already replaced the fuel pump and crank sensor with no luck. After connecting my scan tool, I found a P0601 ‘Internal Control Module Memory Check Sum Error’ code. This code is a direct indicator of an internal PCM failure. Instead of a complicated diagnostic path, the solution was a direct replacement. We installed one of our VIN-programmed PCMs, and the Tahoe fired right up on the first try and ran perfectly. It’s a classic example of how a failing computer can mimic other mechanical problems, and why a reliable, correctly programmed module is the key to an effective repair.
Is Your Truck or SUV Showing These Signs?
A faulty PCM can cause a wide array of problems. If you’re noticing any of the following, it might be time for a replacement:
- ✔ Persistent Check Engine Light (CEL)
- ✔ Diagnostic Trouble Codes (DTCs) like P0601, P0606, or U0100
- ✔ Vehicle won’t start or is difficult to start
- ✔ Rough idling or stalling
- ✔ Noticeable decrease in fuel economy
- ✔ Harsh or incorrect gear shifting
- ✔ Failure to pass an emissions test
A Straightforward Guide to Installation
Replacing your 2003 Isuzu Ascender PCM is a job most DIYers can handle with basic tools. Because we program it for you, no special electronic tools are required for the installation.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the PCM: On most compatible models, the PCM is found in the engine bay, either on the driver’s side near the battery or next to the air filter box.
- Disconnect the Connectors: Carefully unplug the wiring harness connectors from the old module. There are typically release tabs that need to be pressed or lifted.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New Module: Bolt your new, pre-programmed PCM into the mounting bracket.
- Reconnect Everything: Securely plug the wiring harness connectors into the new module. You should hear or feel a click. Reconnect the negative battery terminal.
- Final Step: Your vehicle may need to complete a security relearn procedure, which typically involves turning the key to the ‘On’ position for 10-15 minutes. Consult your owner’s manual for specific instructions.
Will This Fit My Vehicle?
This Powertrain Control Module is a direct-fit replacement for a wide variety of General Motors trucks and SUVs. It is compatible with service numbers 89017750, 12582605, 12589463, 12602802, 89017734, and 28042802. Please review the detailed list below to confirm compatibility with your specific year, make, and model.
ESCALADE 04 Electronic Control Module; (LH front under battery), ID 12602802
ESCALADE EXT 04 Electronic Control Module; (LH front under battery), ID 12602802
HUMMER H2 04 Electronic Control Module; (LH front under battery), SUV
SIERRA 3500 PICKUP 03 Electronic Control Module; (LH front under battery), gasoline, 6.0L
TAHOE 04 Electronic Control Module; (LH front under battery), ID 12602802
YUKON XL 2500 04 Electronic Control Module; (LH front under battery), 6.0L, ID 12602802
ENVOY XL 03 Electronic Control Module; 5.3L (next to air box)
SUBURBAN 2500 03 Electronic Control Module; (LH front under battery), 6.0L
YUKON 04 Electronic Control Module; (LH front under battery), ID 12602802
YUKON XL 2500 05-06 Electronic Control Module; (LH front under battery), 6.0L
AVALANCHE 1500 04 Electronic Control Module; (LH front under battery), ID 12602802
SIERRA 1500 PICKUP 07 Electronic Control Module; classic style (creased door skin), (LH front under battery), w/o hybrid option; w/o 4.3L
SIERRA DENALI 05-06 Electronic Control Module; (LH front under battery)
SUBURBAN 2500 04 Electronic Control Module; (LH front under battery), 6.0L, ID 12602802
YUKON XL 1500 03 Electronic Control Module; (LH front under battery)
YUKON XL 1500 04 Electronic Control Module; (LH front under battery), ID 12602802
ESCALADE ESV 03 Electronic Control Module; (LH front under battery), PCM
ESCALADE ESV 04 Electronic Control Module; (LH front under battery), ID 12602802
HUMMER H2 07 Electronic Control Module; (LH front under battery), powertrain control
SIERRA 3500 PICKUP 05-06 Electronic Control Module; (LH front under battery), gasoline, 6.0L
SIERRA DENALI 03 Electronic Control Module; (LH front under battery)
SILVERADO 2500 PICKUP 05-06 Electronic Control Module; (LH front under battery), gasoline, 6.0L
SUBURBAN 1500 03 Electronic Control Module; (LH front under battery)
HUMMER H2 05-06 Electronic Control Module; (LH front under battery)
SIERRA 2500 PICKUP 04 Electronic Control Module; (LH front under battery), gasoline, 6.0L, ID 12602802
YUKON 03 Electronic Control Module; (LH front under battery)
ESCALADE 05-06 Electronic Control Module; (LH front under battery)
ESCALADE ESV 05-06 Electronic Control Module; (LH front under battery)
SIERRA 2500 PICKUP 05-06 Electronic Control Module; (LH front under battery), gasoline, 6.0L
AVALANCHE 1500 03 Electronic Control Module; (LH front under battery)
SILVERADO 2500 PICKUP 03 Electronic Control Module; (LH front under battery), gasoline, 6.0L
SILVERADO 1500 PICKUP 04 Electronic Control Module; (LH front under battery), w/o hybrid option; w/o 4.3L; ID 12602802
TAHOE 03 Electronic Control Module; (LH front under battery)
TAHOE 05-06 Electronic Control Module; (LH front under battery)
YUKON 05-06 Electronic Control Module; (LH front under battery)
SILVERADO 3500 PICKUP 04 Electronic Control Module; (LH front under battery), gasoline, 6.0L, ID 12602802
SILVERADO 2500 PICKUP 07 Electronic Control Module; classic style (creased door skin), (LH front under battery), gasoline, 6.0L
SILVERADO 3500 PICKUP 05-06 Electronic Control Module; (LH front under battery), gasoline, 6.0L
SUBURBAN 1500 04 Electronic Control Module; (LH front under battery), ID 12602802
ISUZU ASCENDER 03 Electronic Control Module; (LH engine), 5.3L
SIERRA 1500 PICKUP 03 Electronic Control Module; (LH front under battery), w/o 4.3L
SIERRA 1500 PICKUP 04 Electronic Control Module; (LH front under battery), w/o hybrid option; w/o 4.3L; ID 12602802
ESCALADE 03 Electronic Control Module; (LH front under battery), PCM
SSR 03 Electronic Control Module; (next to air box)
SIERRA 2500 PICKUP 03 Electronic Control Module; (LH front under battery), gasoline, 6.0L
SIERRA DENALI 07 Electronic Control Module; classic style (creased door skin), (LH front under battery)
SILVERADO 3500 PICKUP 03 Electronic Control Module; (LH front under battery), gasoline, 6.0L
SUBURBAN 1500 05-06 Electronic Control Module; (LH front under battery)
TRAILBLAZER EXT 03 Electronic Control Module; 5.3L (next to air box)
SILVERADO 1500 PICKUP 05-06 Electronic Control Module; (LH front under battery), w/o hybrid option; w/o 4.3L
SILVERADO 1500 PICKUP 07 Electronic Control Module; classic style (creased door skin), (LH front under battery), w/o hybrid option; w/o 4.3L
SILVERADO 3500 PICKUP 07 Electronic Control Module; classic style (creased door skin), (LH front under battery), gasoline, 6.0L
YUKON XL 1500 05-06 Electronic Control Module; (LH front under battery)
ESCALADE EXT 05-06 Electronic Control Module; (LH front under battery)
SIERRA 1500 PICKUP 05-06 Electronic Control Module; (LH front under battery), w/o hybrid option; w/o 4.3L
SUBURBAN 2500 05-06 Electronic Control Module; (LH front under battery), 6.0L
HUMMER H2 03 Electronic Control Module; (LH front under battery)
SIERRA 2500 PICKUP 07 Electronic Control Module; classic style (creased door skin), (LH front under battery), gasoline, 6.0L
SIERRA 3500 PICKUP 07 Electronic Control Module; classic style (creased door skin), (LH front under battery), gasoline, 6.0L
SIERRA DENALI 04 Electronic Control Module; (LH front under battery), ID 12602802
SILVERADO 1500 PICKUP 03 Electronic Control Module; (LH front under battery), w/o 4.3L
ESCALADE EXT 03 Electronic Control Module; (LH front under battery), PCM
SIERRA 3500 PICKUP 04 Electronic Control Module; (LH front under battery), gasoline, 6.0L, ID 12602802
SILVERADO 2500 PICKUP 04 Electronic Control Module; (LH front under battery), gasoline, 6.0L, ID 12602802
YUKON XL 2500 03 Electronic Control Module; (LH front under battery), 6.0L
Frequently Asked Questions
Do I need to program this module?
No. We handle all the programming for you before shipment. Just provide your vehicle’s VIN at checkout, and it will arrive ready to install with the latest GM software.
Why do you need my VIN?
The VIN (Vehicle Identification Number) allows us to load the exact software and calibrations your specific vehicle requires. This ensures compatibility with your engine, transmission, and other options, making the installation seamless.
Will this fix my check engine light?
If the check engine light is caused by an internal failure of the old PCM (like code P0601), then yes, this new module will resolve the issue. However, if the light is on for another reason (e.g., a bad oxygen sensor), that issue will still need to be addressed separately.
What if my original part number is different from 12582605?
This module is a direct replacement for several service numbers, including 89017750, 12589463, 12602802, and others listed above. As long as your vehicle is on the compatibility list, this module will work perfectly.
Is this a difficult part for a DIYer to install?
Not at all. With basic hand tools and our step-by-step guide, most people can swap the module in under an hour. The most important part is that no programming is needed on your end.