Restore Smooth Shifting to Your Buick Terraza
If your 2006-2007 Buick Terraza is suffering from harsh shifting, getting stuck in gear, or has an illuminated check engine light, a failing Transmission Control Module (TCM) is the most likely culprit. Over my 20 years in the garage, I’ve seen how a faulty TCM can make a reliable minivan feel unpredictable and unsafe. This isn’t just an annoyance; it’s a critical failure that impacts your vehicle’s performance and fuel economy. This direct-fit T42 TCM, service part number 24234503, is the definitive solution to get your Terraza driving like new again.
The biggest headache with module replacement has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. By providing your vehicle’s VIN at checkout, we program the module with the latest GM software updates specifically for your Terraza. It arrives at your door ready for a true plug-and-play installation, saving you hundreds in dealer fees and getting you back on the road faster.
A Technician’s Notebook
I remember a 2007 Chevy Uplander—which uses the same platform as the Terraza—that came into the shop stuck in 3rd gear (limp mode). The customer was quoted over $1000 by a dealer for a new TCM and programming. The scan tool showed a classic P0700 (Transmission Control System Malfunction) code. We installed one of our pre-programmed T42 modules in about 20 minutes right in the parking lot. After a quick battery disconnect to clear the memory and a final scan, the van shifted perfectly. The customer saved a significant amount of money and drove away with a reliable vehicle. This is the exact fix we offer for your 2006-2007 Terraza TCM.
Is Your Terraza Showing These Telltale Signs?
A failing TCM will give you clear warnings. If you’re experiencing any of the following, it’s time to consider a replacement:
- ✔ Abrupt, hard, or jerky gear shifts.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ Vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is on with codes like P0700, P0750, or other solenoid-related faults.
- ✔ Failure to upshift or downshift properly, leading to poor acceleration.
- ✔ A noticeable drop in fuel efficiency.
Your Straightforward TCM Installation Guide
This is a repair that a confident DIYer can complete with basic hand tools. For the 2006-2007 Terraza, the TCM is typically located on the driver’s side of the engine bay, mounted to the strut tower. The entire process should take less than 30 minutes.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the TCM: Find the module on the LH strut tower. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unplug the electrical harnesses. Then, unbolt the module from its mounting bracket.
- Install the New Module: Mount your new, pre-programmed 2006-2007 Terraza TCM in place and securely reconnect the wiring harnesses. You’ll hear a click as they lock in.
- Final Steps: Reconnect the battery terminal. Start the vehicle and allow it to idle for a few minutes. If you have a basic scan tool, use it to clear any stored fault codes.
Verified Vehicle Compatibility List
This T42 Transmission Control Module is a direct replacement for part number 24234503 and is interchangeable with many other GM service numbers. While it is programmed for your specific Terraza, it is also physically compatible with a wide range of GM vehicles, including:
Buick Allure (06-09), LaCrosse (06-09), Lucerne (06-11), Rainier (06-07), Rendezvous (06-07), Terraza (06-07)
Cadillac DTS (06-11)
Chevrolet Avalanche (07-08), Cobalt (06-10), Colorado (08-12), Express Vans (06-14), HHR (06-11), Impala (06-11), Malibu (06-10), Monte Carlo (06-07), Silverado (07-13), SSR (05-06), Suburban (07-08), Tahoe (07-09), Trailblazer (06-09)
GMC Canyon (08-12), Envoy (06-09), Savana Vans (06-14), Sierra (07-13), Yukon (07-09)
Hummer H3 (08-10)
Pontiac G5 (07-10), G6 (06-10), Grand Prix (06-08), Montana (06-09), Pursuit (06)
Saab 9-7X (06-09)
Saturn Aura (07-09), Ion (06-07), Vue (07-10)
What does VIN programming do for my Terraza?
What does VIN programming do for my Terraza?
VIN programming loads your vehicle’s specific software and calibrations onto the TCM before it ships. This ensures the module communicates perfectly with your Terraza’s engine and transmission, providing correct shift points and pressures without needing a trip to the dealer. It makes the installation truly plug-and-play.
Do I need to send my old TCM back?
No, there is no core charge or need to return your old part. You can dispose of it or keep it, making the process simpler and hassle-free for you.
Will this fix a P0700 trouble code?
Yes. The P0700 code is a general fault code indicating the TCM has detected a problem. In most cases where the TCM itself has failed, replacing it with this pre-programmed module will resolve the root cause and allow you to clear the P0700 code and any related transmission codes.
Is this an OEM part?
This is a high-quality replacement part built to meet or exceed original equipment manufacturer (OEM) standards for fit, form, and function. It is guaranteed to perform reliably and is backed by our one-year warranty.