Is your 2006-2007 Buick Terraza suffering from erratic shifting, delayed gear engagement, or getting stuck in limp mode? 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 shift with precision. When it fails, it can lead to poor performance, decreased fuel economy, and potentially catastrophic transmission damage. This OEM-quality T42 Transmission Control Module, part number 24230461, is the definitive solution to restore your vehicle’s drivability and peace of mind.
From the Diagnostic Bay
We once had a 2007 Terraza come into the shop with classic transmission complaints: harsh 1-2 shifts and occasionally getting stuck in 3rd gear. The owner had already spent a small fortune at another shop on a fluid flush and replacing a couple of shift solenoids, but the problem persisted. After a quick scan, we pulled a P0700 code, which is a general transmission fault request. Digging deeper, we found intermittent communication errors with the TCM. Instead of throwing more parts at it, we installed a VIN-programmed T42 module. The vehicle immediately shifted like it just rolled off the factory floor. It’s a textbook example of how diagnosing the electronic controller first can save hundreds in unnecessary mechanical repairs.
Diagnosing Your 2006-2007 Terraza TCM Failure
A faulty transmission module can manifest in various ways, often mimicking mechanical transmission problems. Before condemning your transmission, it’s crucial to consider the TCM as the potential culprit, especially if you’re experiencing electronic-related symptoms. This module is the central command for your 4-speed automatic transmission (like the 4L60E or 4L65E), managing everything from shift points to torque converter lockup based on data from multiple vehicle sensors. When it malfunctions, the entire system is compromised. Our pre-programmed module eliminates the guesswork and provides a reliable, long-term fix.
Symptoms of a Bad Transmission Control Module
- ✔ Erratic Shifting: Experiencing harsh, jerky, or unpredictable gear changes.
- ✔ Delayed Engagement: A noticeable pause when shifting from Park into Drive or Reverse.
- ✔ Stuck in Gear: The vehicle may enter a fail-safe or “limp mode,” often stuck in 2nd or 3rd gear.
- ✔ Warning Lights: The Check Engine Light or a specific transmission warning light is illuminated on your dash.
- ✔ Diagnostic Trouble Codes (DTCs): Common codes include P0700, P0750-P0758 (solenoid circuit faults), or U-codes indicating communication loss.
- ✔ Poor Fuel Economy: Inefficient shifting and failure to engage the torque converter lockup can significantly reduce MPG.
- ✔ No Shifting: The transmission may refuse to upshift or downshift at all.
The Plug-and-Play Advantage: Pre-Programmed for Your VIN
One of the biggest hurdles in replacing modern automotive electronics is the need for expensive dealership programming. We eliminate this step completely. Each module is expertly programmed to your vehicle’s specific Vehicle Identification Number (VIN) before it ships. This ensures that it has the latest GM software updates and is perfectly calibrated for your Terraza’s specific configuration. The result is a true plug-and-play installation—no need for a trip to the dealer or specialized scan tools for programming. This saves you time, money, and the frustration of dealing with incompatible electronics.
This T42 TCM is a direct replacement for a wide range of GM vehicles from 2006-2014, including models like the Chevrolet Impala, GMC Sierra, Saturn Vue, and Pontiac G6. It is interchangeable with numerous part numbers, such as 24252114, 24234503, and 24242391, making it a versatile and reliable choice for your repair.
Installation is straightforward for a DIY mechanic. On the Buick Terraza, the TCM is typically located on the LH strut tower. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one in its place. Reconnect everything, and you’re ready to go. We recommend clearing any stored DTCs with a basic code reader after installation to ensure a clean slate for the new module.
Why is VIN programming so important for this TCM?
VIN programming loads your vehicle’s specific software and calibrations onto the module. This ensures it communicates correctly with the Engine Control Module (ECM) and other vehicle systems, controlling shift points, line pressure, and torque converter lockup exactly as the manufacturer intended. Without it, the transmission will not function correctly.
Is this a new or used part?
This is a high-quality, OEM-standard replacement part that has been meticulously inspected and prepared to ensure it meets or exceeds original performance specifications. It is not a new part from the original manufacturer but is guaranteed to function as a reliable replacement.
Will this fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem and requested the Check Engine Light to be turned on. While this module often resolves the root cause of a P0700, it’s essential to scan for other transmission-specific codes (like P07xx) to confirm the TCM or a related circuit is the issue.
Where is the TCM located on my 2006 Terraza?
On the 2006-2007 Buick Terraza, the Transmission Control Module is typically found in the engine compartment, mounted to the driver’s side (LH) strut tower. Always confirm the location on your specific vehicle before beginning the replacement.
Do I need to return my old module?
No, there is no core charge for this part. You can keep your old module, eliminating the hassle and expense of shipping it back.