Restore Peak Performance to Your Saturn S-Series
Is your 2000, 2001, or 2002 Saturn S-Series suffering from mysterious and frustrating issues? A faulty Engine Control Module (ECM) is often the hidden culprit behind problems like a persistent Check Engine Light, erratic engine behavior, stalling, or even a complete no-start condition. This vital component is the brain of your vehicle’s engine, and when it fails, it can cause a cascade of problems. This listing offers a reliable, tested, and pre-programmed replacement Saturn S Series ECM to get your vehicle back on the road and running as it should.
This unit is a direct replacement for multiple original equipment part numbers, including 21025110, 21025128, 21009349, and 21024986. We take the guesswork and hassle out of the replacement process. Upon purchase, simply provide us with your vehicle’s Vehicle Identification Number (VIN). Our technicians will then flash the module with the latest, most stable software updates directly from GM, ensuring it is perfectly matched to your car’s specific configuration. This critical programming step means no expensive trips to the dealership for coding—it arrives ready for installation.
From the Diagnostic Bay
We had a 2001 Saturn SL2 towed in that had stumped two other shops. The car would start and run for a few minutes, then die suddenly and refuse to restart for hours. There were no consistent trouble codes, just a general communication error that would pop up intermittently. We checked all the usual suspects—fuel pump, crank sensor, ignition system—and everything tested fine. On a hunch, we monitored the data stream from the ECM and noticed that the 5-volt reference signal to the sensors would suddenly drop out right before the engine stalled. After swapping in a known-good, programmed ECM, the car ran perfectly. The original ECM had an internal thermal fault that only appeared after it warmed up. It’s a classic example of how a failing computer can create ghost-like symptoms that are impossible to trace without addressing the core component.
Is Your Saturn S-Series Showing These Symptoms?
- ✔ Persistent Check Engine Light (CEL) that won’t clear
- ✔ Engine stalling or shutting off unexpectedly while driving
- ✔ Difficulty starting the engine or a no-start condition
- ✔ Poor fuel economy and noticeable loss of power
- ✔ Rough or erratic idling
- ✔ Harsh or incorrect shifting from the automatic transmission
- ✔ Communication errors when using a diagnostic scan tool
Why Choose This Programmed Saturn S Series ECM?
This isn’t just a used part pulled from a salvage yard. It’s a comprehensive solution. Each module is sourced from a salvaged vehicle and meticulously inspected. The real value lies in our professional programming service. By flashing the computer with your car’s VIN, we ensure all factory settings for the engine, transmission, and emissions systems are correctly loaded. This prevents compatibility issues that can arise from installing a non-programmed module from another vehicle. It’s the most reliable and cost-effective way to solve complex electronic issues and restore your Saturn’s original drivability.
Simple, Hassle-Free Process:
- Place Your Order: Add this ECM to your cart and complete the checkout process.
- Provide Your VIN: Reply to your order confirmation email with your 17-digit VIN, or include it in the notes at checkout.
- We Program & Ship: Our technicians will program the module specifically for your vehicle and ship it out promptly.
This module is a direct fit for 2000-2002 Saturn S-Series models equipped with an automatic transmission. It is located in the engine compartment on the driver’s side, behind the battery. Replacing your faulty Saturn S Series ECM is a straightforward job for a competent DIYer or any professional mechanic. Get your Saturn running right again with this fully programmed, ready-to-install engine computer.
Frequently Asked Questions
Why do I need to provide my VIN?
Your Vehicle Identification Number (VIN) contains critical information about your car’s specific options, engine type, transmission, and emissions equipment. We use the VIN to load the exact GM factory software onto the ECM, ensuring it communicates perfectly with all other modules in your vehicle for seamless operation.
Is any additional programming required after installation?
No. This ECM comes pre-programmed to your VIN and is ready for installation. In most cases, a security relearn procedure may be necessary, which can typically be done without special tools and instructions can be easily found online. This ensures the new ECM syncs with your car’s anti-theft system.
Where is the ECM located on a 2000-2002 Saturn S-Series?
The Electronic Control Module is located in the engine compartment on the driver’s side (LH side). You will find it situated behind the battery tray. You will need to remove the battery to gain access to it.
Will this fix my transmission shifting problems?
In many cases, yes. The ECM works in conjunction with the Transmission Control Module (TCM) to control shift points and line pressure. A faulty ECM can send incorrect data, leading to poor shifting performance. If the root cause of your issue is the ECM, this part will resolve it.
Which part numbers does this module replace?
This ECM is a direct, compatible replacement for the following GM part numbers: 21025110, 21025128, 21009349, and 21024986. If your original module has any of these numbers, this part will work for your vehicle.