Restore Your Pontiac’s Smooth Shifting Performance
If your 2006-2010 Pontiac G6 is suffering from erratic shifting, getting stuck in gear, or throwing transmission codes, a failing Transmission Control Module (TCM) is the most likely culprit. As a technician with over two decades of diagnostic experience, I’ve seen firsthand how a faulty TCM can cripple an otherwise reliable vehicle. This isn’t just an annoyance; it’s a critical failure that affects drivability and safety. This T42 series TCM, part number 24238856, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play repair.
This module is the brain of your automatic transmission, responsible for managing shift points, torque converter clutch engagement, and line pressure. When it fails, communication between the engine and transmission breaks down, leading to the frustrating symptoms you’re likely experiencing. Our module restores that crucial link, ensuring your G6 drives as smoothly as it did from the factory. By ordering this pre-programmed 2006-2010 G6 Transmission Control Module, you bypass the expensive and time-consuming trip to a dealership for programming.
A Technician’s Notebook: The Phantom Shifting Problem
A customer brought in a 2008 Pontiac G6 with a classic complaint: intermittent harsh shifting and a check engine light that would come and go. They’d already replaced a couple of solenoids with no luck. The scanner showed a general P0700 (Transmission Control System Malfunction) code, but nothing specific. After confirming the fluid was clean and at the correct level, I focused on the TCM. These T42 modules, especially when exposed to years of engine bay heat cycles, can develop internal circuit faults that don’t always throw a specific component code. Replacing the original with a correctly VIN-programmed TCM solved the issue on the first try. The car’s shift logic was immediately restored—a perfect example of why starting with the brain is often the right move.
Is Your G6 Showing These Symptoms?
- ✔ Harsh, banging shifts or delayed gear engagement.
- ✔ Vehicle is stuck in “limp mode” (usually 2nd or 3rd gear).
- ✔ The Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) like P0700, P0750, or other solenoid-related faults are present.
- ✔ Complete loss of shifting, either up or down.
- ✔ Poor fuel economy and a feeling of sluggishness.
DIY Installation: No Special Tools Required
- ✔ Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and reset the system.
- ✔ Locate the Module: On the Pontiac G6, the TCM is typically found on the driver’s side, mounted to the strut tower in the engine bay.
- ✔ Disconnect and Remove: Carefully unplug the electrical connectors. Note the tab locations to avoid damage. Then, unbolt the module from its mounting bracket.
- ✔ Install the New TCM: Mount your new, pre-programmed 2006-2010 G6 Transmission Control Module and securely reconnect the electrical harnesses. You should hear a click as they lock in place.
- ✔ Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s best practice to use a basic OBD2 scan tool to clear any stored transmission codes to ensure a clean slate for the new part.
Verified Vehicle Compatibility
This module is a direct replacement for part number 24238856 and other interchangeable numbers across a wide range of GM vehicles. While this page focuses on the 2006-2010 G6 Transmission Control Module, it also fits models like the Chevrolet Cobalt, HHR, Malibu; Saturn Aura, Ion, Vue; and Pontiac G5. Please see the detailed fitment list below to confirm compatibility with your specific vehicle and engine.
Frequently Asked Questions
Why is VIN programming so important?
VIN programming loads your vehicle’s specific software and calibrations onto the module. This ensures it communicates perfectly with your car’s engine computer and other systems, controlling shift points and pressures exactly as the manufacturer intended. Without it, the module won’t work correctly, if at all.
Do I need to take this part to a dealer after installation?
No. Our service includes pre-programming the module to your VIN before we ship it. This eliminates the need for any additional programming at a dealership, saving you time and hundreds of dollars.
Is this a difficult part to replace myself?
For most DIYers with basic tools, this is a very straightforward job. The module is easily accessible in the engine bay on the G6, and the entire process usually takes less than 30 minutes.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. In many cases where no other specific codes are present, a failing TCM is the root cause. Replacing it often resolves the P0700 code and the underlying shifting issues.
What is your warranty policy?
This transmission control module is backed by our standard one-year warranty, giving you peace of mind and confidence in your repair.
Is there a core charge for my old part?
No, we do not require a core return. You can keep your old part without any additional charges or hassle.