Restore Peak Performance to Your GM Transmission
Is your Chevrolet Trailblazer, GMC Envoy, or other GM vehicle suffering from erratic shifting, getting stuck in gear, or displaying transmission-related warning lights? These are classic signs of a failing Transmission Control Module (TCM). The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every gear change, managing torque converter lockup, and ensuring smooth, efficient operation. When it fails, it can mimic the symptoms of a catastrophic mechanical failure, leading to incorrect diagnoses and unnecessary, costly repairs.
This genuine OEM-quality T42 Transmission Control Module, service part number 24230461, is the definitive solution for restoring your vehicle’s transmission to its factory-set performance. It’s not just a replacement part; it’s a complete, plug-and-play fix, pre-programmed to your vehicle’s specific Vehicle Identification Number (VIN). This critical programming step ensures seamless integration with your vehicle’s powertrain and other electronic systems, eliminating the need for an expensive trip to the dealership for programming.
From the Diagnostic Bay
We had a 2008 Chevy Trailblazer come into the shop towed on a flatbed. The owner was convinced his 4L60E transmission was completely shot. It was stuck in third gear (limp mode), the check engine light was on, and it shifted with a violent bang when going from Park to Drive. Another shop had quoted him over $3,000 for a transmission rebuild. We hooked up our scan tool and immediately saw a P0700 code and several solenoid communication errors. Instead of tearing down the transmission, we checked the TCM. After a quick inspection of the wiring, we swapped in one of our VIN-programmed T42 modules. In under 30 minutes, the Trailblazer was shifting perfectly, all codes were cleared, and the customer drove away having saved thousands of dollars. It’s often the brain, not the brawn, that’s the issue.
Symptoms of a Failing Trailblazer Transmission Control Module
- ✔️ Harsh, delayed, or unpredictable gear shifts that make driving uncomfortable and unsafe.
- ✔️ The vehicle is stuck in a single gear, commonly known as “limp mode,” to prevent further damage.
- ✔️ Illumination of the Check Engine Light or a dedicated transmission warning light on your dashboard.
- ✔️ Diagnostic Trouble Codes (DTCs) such as P0700 (Transmission Control System Malfunction) or specific solenoid codes (e.g., P0751, P0756).
- ✔️ A noticeable decrease in fuel economy as the transmission operates inefficiently.
- ✔️ Inability to shift into higher or lower gears, or a complete loss of communication with the transmission.
The Power of VIN Programming
Many replacement modules require post-installation programming at a dealership, adding time, cost, and hassle to your repair. Our process eliminates this step entirely. We use the latest GM software updates to load your vehicle’s specific VIN onto the module before it ships. This ensures that the TCM has the correct shift strategies, pressure control parameters, and software calibrations for your exact vehicle configuration. The result is an immediate, out-of-the-box solution that performs as the original manufacturer intended.
Simple Installation for DIY and Professionals
Installation is a straightforward process that can typically be completed in under an hour with basic hand tools. The TCM is located in the engine compartment, with common locations being on the LH strut tower, next to the battery, or under the air cleaner box, depending on your specific model. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one in its place. Once reconnected, the pre-programmed module is ready to go. We recommend using a scan tool to clear any stored DTCs after installation is complete. Best of all, there is no core charge—you can keep or dispose of your old part without any additional fees.
This module is a direct replacement for a wide range of GM vehicles and interchanges with numerous part numbers, including 24252114, 24234503, 24242391, and more. Restore the precise, smooth shifting your vehicle was built with. Order your VIN-programmed T42 TCM today and get back on the road with confidence.
Frequently Asked Questions
What is VIN programming and why is it important?
VIN programming is the process of loading your vehicle’s unique 17-digit Vehicle Identification Number and its associated software calibrations onto the module. This is critical because it ensures the TCM communicates correctly with your engine computer and other systems, controlling shift points and pressures exactly as the manufacturer designed for your specific model, engine, and axle ratio.
Do I need to take my vehicle to a dealer after installing this TCM?
No. This Transmission Control Module comes pre-programmed to your VIN. This makes it a true plug-and-play solution, saving you the time and expense of a dealership visit for programming.
Where is the TCM located on my 2007 Trailblazer?
On 2006-2009 Chevrolet Trailblazer models, the Transmission Control Module is typically located in the engine compartment on the driver’s side (LH), often near the firewall or strut tower.
Is there a core charge for this part?
No, there is no core charge associated with this module. You are not required to return your old part, which simplifies the repair process for you.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While a faulty TCM is a very common cause for this code, it can also be triggered by other transmission issues. Replacing a known-bad TCM is often the correct fix for a P0700 code, especially when accompanied by other transmission-specific codes or shifting symptoms.