Restore Your Monte Carlo’s Smooth Shifting Performance
Is your 2006-2007 Chevrolet Monte Carlo suffering from harsh shifting, getting stuck in gear, or throwing transmission codes like P0700? You’re not alone. After years of service, the factory Transmission Control Module (TCM), the electronic brain of your automatic transmission, can fail. This leads to frustrating and potentially unsafe driving conditions. This OEM-quality T42 TCM, part number YNXS, is the definitive solution, arriving pre-programmed to your vehicle’s specific VIN for a true plug-and-play repair.
As a technician with over two decades of experience, I’ve seen countless GM vehicles with these exact symptoms. The T42 module is responsible for every aspect of your transmission’s behavior—from shift points to torque converter lockup. When it falters, the symptoms can range from annoying to debilitating. Our VIN programming service eliminates the need for an expensive trip to the dealership for coding, saving you time, money, and hassle. Simply install the module, and you’re ready to go.
Case Study: A Tricky Diagnosis
A customer brought in their ’06 Monte Carlo with an intermittent ‘bang’ when shifting from 2nd to 3rd gear and a persistent P0753 (Shift Solenoid ‘A’ Electrical) code. They had already replaced the solenoid twice with no luck. After confirming the internal wiring harness was good, we suspected the TCM. The location under the air cleaner housing exposes these modules to constant heat cycles, which can degrade internal solder joints over time. We installed one of our VIN-programmed T42 modules, and the problem was solved instantly. The pre-programming ensured the new module communicated perfectly with the car’s powertrain, restoring crisp, clean shifts.
Key Signs Your T42 Module is Failing
- ✔ Harsh, jerky, or delayed gear shifts.
- ✔ Vehicle is stuck in “limp mode” (usually 2nd or 3rd gear).
- ✔ Check Engine Light or Transmission Warning Light is on.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as P0700, P0750, P0753, P0758, or other solenoid-related faults.
- ✔ Inconsistent upshifting or downshifting.
- ✔ A noticeable drop in fuel economy.
- ✔ The transmission feels like it’s slipping between gears.
A Straightforward Guide to Installation
For the 2006-2007 Monte Carlo, this is a job most DIY enthusiasts can handle in under 30 minutes with basic tools. The module is located under the lower air cleaner housing.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and reset the system.
- Access the Module: Remove the air cleaner assembly to gain clear access to the TCM mounted below it.
- Disconnect and Remove: Carefully unplug the electrical connectors from the old TCM. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, VIN-programmed TCM into place and securely reconnect the electrical harnesses. You’ll hear a ‘click’ when they’re seated.
- Final Steps: Reinstall the air cleaner assembly and reconnect the battery terminal. Start the vehicle and allow it to idle for a few minutes. While not always necessary, using a scan tool to clear any stored codes is good practice.
Verified Vehicle Compatibility
This T42 TCM is a direct-fit replacement for a wide range of General Motors vehicles. While this page focuses on the 2006-2007 Monte Carlo TCM, it is also compatible with the following models. Please verify your part number (YNXS or an interchange number) for a perfect match.
- Chevrolet: Monte Carlo (06-07), Impala (06-11), Silverado, Tahoe, Suburban, Express, HHR, Cobalt, Colorado, Avalanche
- GMC: Sierra, Yukon, Savana, Canyon, Envoy
- Buick: LaCrosse (06-09), Lucerne (06-11), Allure, Rainier, Rendezvous
- Pontiac: G6 (06-10), Grand Prix (06-08), G5, Pursuit
- Cadillac: DTS (06-11)
- Saturn: Vue, Aura, Ion
- And others: Hummer H3, Saab 9-7X, Isuzu Ascender
Frequently Asked Questions
Why is VIN programming so important?
VIN programming loads your vehicle’s exact software and calibrations onto the module. This ensures it communicates correctly with the engine computer and other systems, guaranteeing proper shift patterns, torque converter operation, and overall performance without any additional setup.
Is this a difficult part to install myself?
Not at all. For a Monte Carlo, it’s located under the air cleaner housing and requires only basic hand tools. The entire process typically takes less than half an hour, making it a great DIY-friendly repair.
Will this module fix a P0700 trouble code?
A P0700 code is a general fault code indicating the TCM has detected a problem. While this module often resolves the root cause (like a faulty solenoid driver), you should always diagnose any other specific codes (e.g., P0753) that appear alongside it. In many cases, a faulty TCM is the primary issue.
Do I need to return my old TCM?
No, there is no core charge for this part. You can keep your old module without any hassle or extra fees.
What kind of warranty is included?
This transmission control module is backed by our one-year, hassle-free warranty, giving you peace of mind in your repair.
Are there other part numbers this is compatible with?
Yes, this module interchanges with numerous GM part numbers, including 24252114, 24234503, 24230461, 24240449, and YNXS among others. Matching one of these numbers confirms compatibility.