Restore Your GM’s Performance and Reliability
Is your 2003-2005 Monte Carlo suffering from a persistent Check Engine Light, erratic engine behavior, or poor fuel economy? As a technician with over 20 years of experience, I’ve seen countless drivers chase symptoms by replacing sensors and spark plugs, only to find the root cause was a failing Powertrain Control Module (PCM). The PCM is the brain of your engine, and when it malfunctions, the entire system suffers. This module, part number 89017735, is the definitive solution to get your vehicle running smoothly again.
We take the guesswork and high cost out of the repair. Unlike a generic module from a parts store or salvage yard, this PCM arrives at your door fully programmed with the latest GM software updates, specifically matched to your vehicle’s VIN. This means no expensive trip to the dealership for programming. It’s a direct-fit, ready-to-install solution designed to restore factory performance and efficiency.
A Technician’s Notebook
I remember a 2004 Impala with the 3.4L V6 that came into my bay with a bizarre set of complaints: intermittent stalling at red lights, hard shifting, and a Check Engine Light that would come and go. The owner had already replaced the MAF sensor and the throttle position sensor. My scan tool showed a P0601 (Internal Control Module Memory Check Sum Error) code stored, but it wasn’t always active. After verifying all the power and ground circuits to the PCM were solid, I knew the module itself was failing internally. We installed a VIN-programmed PCM just like this one, performed the security relearn, and the car ran perfectly. It’s a classic case where the computer itself is the point of failure.
Common Signs of a Failing PCM
If you’re experiencing any of the following, a faulty PCM could be the culprit. A failing module can cause a wide range of issues that often mimic sensor failures.
- ✔ Persistent Check Engine Light (CEL)
- ✔ Stored diagnostic trouble codes (DTCs) like P0601, P0606, or U0100
- ✔ Engine stalling, stumbling, or rough idling
- ✔ Noticeable decrease in fuel efficiency
- ✔ Harsh or erratic automatic transmission shifting
- ✔ Failure to pass state emissions inspections
- ✔ Complete no-start condition where the engine cranks but won’t fire
A Straightforward Guide to Installation
Replacing the PCM is a manageable job for a DIY enthusiast. Following these steps will ensure a smooth installation process.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the PCM: On most of these vehicles, the PCM is located in the engine compartment, often on the driver’s side inside the air filter housing. Consult a repair manual for your specific model if you’re unsure.
- Disconnect Connectors: Carefully unclip and remove the electrical wiring harnesses from the old PCM. These connectors have locking tabs that must be released before pulling.
- Remove the Old Module: Unbolt the old PCM from its mounting bracket and remove it from the vehicle.
- Install the New PCM: Mount your new, pre-programmed PCM onto the bracket and securely bolt it in place.
- Reconnect Everything: Plug the wiring harnesses back into the new module until they click, and then reconnect the negative battery terminal.
- Perform Security Relearn: You will need to perform a simple key-on/key-off security relearn procedure. This typically involves turning the key to the ‘ON’ position for 10-15 minutes, then ‘OFF’ for 10 seconds, and repeating this cycle three times. This allows the new PCM to recognize your vehicle’s anti-theft system.
Verified Vehicle Compatibility
This module is a direct replacement for part numbers 12583827 and 12583826. It is guaranteed to fit the following models. Please provide your VIN upon purchase to ensure correct programming.
- Alero: 2003-2004 (3.4L)
- Aztek: 2003-2005
- Bonneville: 2004-2005 (3.8L)
- Century: 2003-2005
- Grand Am: 2003-2005 (3.4L)
- Grand Prix: 2003 (3.1L)
- Impala: 2003-2005
- LeSabre: 2004-2005
- Malibu: 2003
- Montana: 2003-2005
- Monte Carlo: 2003-2005
- Park Avenue: 2004-2005
- Rendezvous: 2003-2005
- Silhouette: 2003-2004
- Venture: 2003-2005
Frequently Asked Questions
How do I provide my VIN?
After you complete your purchase, you can send us your 17-digit Vehicle Identification Number (VIN) through the messaging system. We cannot program and ship the module without it.
Is this module truly plug-and-play?
Yes, it comes programmed to your VIN. The only additional step required after physical installation is a simple security relearn procedure, which does not require any special tools. Instructions are included.
Will this fix my transmission shifting problems?
The PCM also controls transmission functions. If your shifting issues are caused by faulty electronic commands from the PCM, this replacement will resolve them. It cannot fix internal mechanical failures within the transmission itself.
What if my original part number isn’t 89017735?
This module is also a direct replacement for service numbers 12583827 and 12583826. As long as your vehicle is on the compatibility list, this module will work once programmed to your VIN.
Do I need to do anything after the security relearn?
After the security relearn is complete, the vehicle should start and run normally. We recommend driving the vehicle for 20-30 minutes to allow the PCM to learn all the specific parameters of your engine for optimal performance.