If your 2006-2007 Buick Terraza is suffering from erratic shifting, getting stuck in gear, or has an illuminated check engine light, you’re likely dealing with a failed Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen how a faulty TCM can sideline a perfectly good vehicle. This isn’t just an inconvenience; it’s a critical failure that compromises drivability and safety. This replacement T42 TCM, part number YNXS, is the reliable, straightforward solution to restore your minivan’s performance and get your family back on the road safely.
This isn’t just a part in a box. We pre-program it to your Terraza’s specific Vehicle Identification Number (VIN) before it ships. This crucial step eliminates the need for expensive dealership programming or specialized scan tools, making it a true plug-and-play fix. It’s designed to directly address the root cause of many common transmission-related diagnostic trouble codes (DTCs), ensuring your vehicle operates exactly as the manufacturer intended.
A Technician’s Notebook
I remember a 2007 Buick Terraza that came into my shop. The owner was frustrated because the van would intermittently refuse to shift out of 2nd gear, making highway driving impossible. They had already replaced a shift solenoid with no luck. After a quick scan, I saw the classic P0700 (Transmission Control System Malfunction) code. Experience pointed directly to the TCM. Instead of a costly and time-consuming dealership visit, we installed one of our VIN-programmed modules. The entire job took less than 20 minutes. The van shifted perfectly on the test drive, and the customer was relieved to have a simple, permanent fix without the dealership price tag. That’s the value of a correctly prepared part.
Is Your Terraza Exhibiting These Transmission Faults?
A failing 2006-2007 Terraza Transmission Module will often present clear symptoms. If you’re experiencing any of the following, the TCM is the most likely culprit:
- âś” Harsh, slamming shifts or delayed gear engagement.
- âś” Vehicle is stuck in “limp mode” (usually 2nd or 3rd gear).
- âś” The check engine light is on with codes like P0700, P0750, or other solenoid-related faults.
- âś” Complete failure to upshift or downshift.
- âś” A noticeable drop in fuel economy.
- âś” Intermittent loss of communication with the transmission module.
A Straightforward Guide to Installation
One of the best features of this module is its ease of installation. For the Buick Terraza, the TCM is conveniently located on the driver’s side strut tower. You can complete this repair in your own garage with basic hand tools.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts.
- Locate the Module: Open the hood and find the TCM mounted to the left-hand (driver’s side) strut tower.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old module. Then, unbolt the module from its mounting bracket.
- Install the New Module: Mount your new, pre-programmed TCM onto the bracket and securely plug in the electrical connectors.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s always a good practice to use a basic scan tool to clear any stored fault codes from the vehicle’s memory.
Verified Vehicle Compatibility
This T42 Transmission Control Module is a direct fit for the following vehicles and configurations. Please verify your model and the noted location before ordering.
- TERRAZA 2006-2007 (Transmission; LH strut tower)
- ALLURE 2006-2009 (Transmission; lower air cleaner housing)
- AVALANCHE 1500 2007-2008 (Transmission; next to battery)
- CANYON 2008-2012 (Transmission; RH rear engine compartment)
- COBALT 2006-2010 (Transmission; LH strut tower)
- COLORADO 2008-2012 (Transmission; RH rear engine compartment)
- DTS 2006-2011 (Transmission; RH front engine compartment)
- ENVOY 2006-2009 (Transmission; LH engine compartment)
- EXPRESS VANS 1500/2500/3500 2006-2014 (Transmission; RH engine compartment)
- G5 2007-2010 (Transmission; LH strut tower)
- G6 2006-2010 (Transmission; LH strut tower)
- GRAND PRIX 2006-2008 (Transmission; lower air cleaner housing)
- HHR 2006-2011 (Transmission; LH engine compartment)
- HUMMER H3 2008-2010 (Transmission; RH rear engine compartment)
- IMPALA 2006-2011 (Transmission; lower air cleaner housing)
- ION 2006-2007 (Transmission; behind LH strut tower)
- LACROSSE 2006-2009 (Transmission; lower air cleaner housing)
- LUCERNE 2006-2011 (Transmission; LH engine compartment)
- MALIBU 2006-2010 (Transmission; LH frame rail)
- MONTE CARLO 2006-2007 (Transmission; lower air cleaner housing)
- MONTANA 2006-2009 (Transmission; LH strut tower)
- RAINIER 2006-2007 (Transmission)
- RENDEZVOUS 2006-2007 (Transmission; air cleaner box)
- SAAB 9-7X 2006-2009 (Transmission; LH engine compartment)
- SAVANA VANS 1500/2500/3500 2006-2014 (Transmission; RH engine compartment)
- SIERRA & SILVERADO TRUCKS 2007-2013 (See specific options in base data)
- TAHOE & YUKON 2007-2009 (Transmission; next to battery)
- TRAILBLAZER 2006-2009 (Transmission; LH engine compartment)
- UPLANDER 2006-2009 (Transmission; LH strut tower)
- VUE 2007-2010 (See specific options in base data)
Frequently Asked Questions
What does ‘VIN Programmed’ mean for my Terraza?
It means we load your vehicle’s unique VIN into the module before shipping. This ensures the TCM has the correct software and calibration for your specific engine, transmission, and options, allowing it to work perfectly right out of the box without a trip to the dealer.
Do I need any special tools for this installation?
No. Basic hand tools like a socket set and ratchet are all that’s required to access and replace the module on a Buick Terraza. No programming tools are needed.
Is there a core charge for this part?
No, there is no core charge. You are not required to send your old, faulty module back to us, which simplifies the process for you.
Will this fix a P0700 check engine light code?
Yes, in many cases. The P0700 code is a general fault code indicating the TCM has detected a problem. Replacing a faulty 2006-2007 Terraza Transmission Module is often the direct fix for this and related transmission codes.