If you’re dealing with the frustration of a 2006-2007 Terraza that slams into gear, refuses to shift, or is stuck in limp mode, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen firsthand how a failing Transmission Control Module (TCM) can bring a perfectly good vehicle to a standstill. The TCM is the brain of your automatic transmission, and when it malfunctions, it creates a cascade of problems that can feel overwhelming. This T42 Transmission Control Module, part number 24240449, is the definitive, hassle-free solution to restore your minivan’s performance and your peace of mind.
The biggest roadblock for this repair used to be the dealership. You’d have to buy the part, have your vehicle towed in, and then pay hundreds for them to program it. We’ve eliminated that entire process. We pre-program this module to your vehicle’s specific VIN before it even ships. That means when it arrives at your door, it’s ready for a direct, plug-and-play installation. No extra fees, no special tools, and no trip to the dealer. You get a reliable part that communicates flawlessly with your Terraza’s engine computer, just like the original.
Case Study: The Intermittent Terraza
A customer brought in a 2007 Terraza with a complaint that stumped two other shops. The van would drive perfectly for days, then suddenly start shifting hard and throw a P0700 code. They’d clear it, and it would be fine again. After checking the wiring harness and solenoids—which all tested good—I suspected the TCM. These modules can develop internal micro-fractures from heat cycles, causing intermittent connection failures. We installed one of our pre-programmed T42 TCMs, and the problem vanished for good. It wasn’t a mechanical failure inside the transmission; it was the brain telling the body to do the wrong thing. This fix saved the customer from a potential transmission rebuild costing thousands.
Is Your Terraza Exhibiting These Telltale Signs?
A faulty TCM can manifest in several ways. If you’re noticing any of the following, it’s a strong indicator that your module needs replacement:
- ✔ Harsh, banging, or erratic gear shifts.
- ✔ The vehicle is stuck in a single gear (often 2nd or 3rd), also known as “limp mode.”
- ✔ Check Engine Light or Transmission Warning Light is illuminated on the dash.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700 (Transmission Control System Malfunction), P0750-P0758 (Shift Solenoid errors), or other transmission-related codes.
- ✔ Delayed engagement when shifting from Park to Drive or Reverse.
- ✔ A noticeable decrease in fuel economy due to inefficient shifting.
Your 30-Minute Path to Smooth Shifting
Installing your new 2006-2007 Terraza TCM is a straightforward job that most DIYers can handle in their own driveway. For the Terraza, the module is conveniently located.
- Safety First: Before you begin, disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the vehicle’s computer systems.
- Locate the TCM: On your 2006-2007 Terraza, the Transmission Control Module is typically found mounted to the left-hand (driver’s side) strut tower in the engine bay.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Press the release tabs firmly. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place. Reconnect the electrical connectors, ensuring they click securely into place.
- Final Steps: Reconnect the negative battery terminal. While the module is plug-and-play, it’s always a good practice to use a basic OBD2 scan tool to clear any stored fault codes from the previous failure. Start the vehicle and enjoy your restored, smooth-shifting transmission!
Verified Fitment for Your Vehicle
This module is a direct replacement for part number 24240449 and other interchangeable numbers. While this page is focused on the 2006-2007 Terraza TCM, this part also fits a wide range of other GM vehicles. Please verify your vehicle in the list below:
- TERRAZA: 2006-2007 (Transmission; LH strut tower)
- UPLANDER: 2006-2009 (Transmission; LH strut tower)
- MONTANA: 2006-2009 (Transmission; LH strut tower)
- …and many other GM cars, trucks, and SUVs from 2006-2014. Please check the full compatibility list or contact us with your VIN.
Frequently Asked Questions
Do I need to have this module programmed by a dealer?
No. This is the primary benefit of our service. We pre-program the module to your vehicle’s VIN before shipping, so it arrives ready for immediate, plug-and-play installation. You will save hundreds of dollars and avoid a trip to the dealership.
Is this a difficult part to install myself?
Not at all. For most DIY enthusiasts with basic hand tools, this is a very manageable job that typically takes less than 30 minutes. On the Terraza, the module is easily accessible in the engine compartment.
What is a core charge? Do I need to send my old part back?
There is absolutely no core charge for this part. You can keep your old module or dispose of it yourself, making the process simpler and more convenient for you.
Will this fix a P0700 check engine light code?
Yes, in most cases. The P0700 code is a general fault code indicating the TCM has detected a problem. If the TCM itself is the source of the failure, replacing it with this programmed unit will resolve the issue and allow the code to be cleared permanently.
What if I have questions during installation?
We’re here to help. Our team of experts is available to provide support and answer any questions you may have about the part or the installation process. Your satisfaction is our top priority.