Is Your Chevrolet HHR Shifting Erratically?
If you’re experiencing harsh shifting, delayed gear engagement, or your 2006-2011 Chevrolet HHR is stuck in limp mode, a faulty Transmission Control Module (TCM) is the most likely cause. The TCM is the electronic brain of your automatic transmission, responsible for managing shift points, torque converter clutch lockup, and fluid pressure. When it fails, it can cause a cascade of problems that affect your vehicle’s drivability, fuel economy, and overall reliability.
This genuine OEM-quality T42 TCM, service part number 24243901, is the definitive solution to restore your vehicle’s transmission performance. It arrives expertly programmed to your vehicle’s specific VIN, eliminating the need for expensive dealership programming. This plug-and-play module ensures seamless integration and immediate restoration of smooth, precise shifting.
Solving Common T42 TCM Failures in Your GM Vehicle
The T42 module was used across a wide range of GM vehicles, and its failure symptoms are well-documented by technicians. A failing module can trigger a check engine light with Diagnostic Trouble Codes (DTCs) like P0700, which indicates a general transmission fault, or more specific codes related to shift solenoids (e.g., P0750, P0751, P0752). Drivers often report the vehicle feeling like it’s starting in the wrong gear or refusing to upshift, leading to poor acceleration and high RPMs on the highway. This isn’t just an inconvenience—it’s a critical issue that can lead to further transmission damage if not addressed. Our replacement 2006-2011 HHR Transmission Module is engineered to resolve these specific electronic failures and prevent future issues.
From the Diagnostic Bay
We recently had a 2009 HHR come into the shop with classic limp mode symptoms—stuck in 3rd gear with a P0700 code. The owner had already spent a few hundred dollars replacing a couple of shift solenoids based on a generic code reader’s output, but the problem persisted. After a quick scan with professional equipment, we identified erratic data coming from the TCM itself. The internal processor was failing intermittently. We installed one of our VIN-programmed T42 modules, cleared the codes, and the car was shifting perfectly within 30 minutes. It’s a common story: chasing mechanical parts when the electronic controller is the true source of the fault.
Symptoms of Failure and Product Benefits
- ✔ Eliminate Harsh Shifting: Puts an end to jarring, delayed, or slipping gear changes for a smooth ride.
- ✔ Fix Check Engine Lights: Pre-programmed to resolve common transmission-related DTCs, including P0700 and various solenoid codes.
- ✔ Escape Limp Mode: Restores full gear functionality, getting your vehicle out of a fail-safe mode (stuck in 2nd or 3rd gear).
- ✔ Plug-and-Play Installation: Arrives programmed to your vehicle’s VIN, requiring no additional dealership visits for software flashing.
- ✔ Restore Fuel Economy: Ensures efficient shifting and proper torque converter lockup to bring your MPG back to factory levels.
- ✔ OEM-Standard Quality: Built to meet or exceed original equipment specifications for lasting durability and performance, backed by a one-year warranty.
- ✔ No Core Charge: Keep your old part without the hassle or expense of a core return.
Easy Installation for DIY and Professionals
Replacing the 2006-2011 HHR Transmission Module is a straightforward process. On the HHR, the TCM is typically located in the left-hand (driver’s side) engine compartment. The process involves disconnecting the battery to ensure safety and reset the vehicle’s electronic systems, unplugging the electrical connectors from the old module, unbolting it, and installing the new one in its place. Once the new module is connected and the battery is reconnected, the vehicle is ready to go. While many codes will clear automatically, it’s always best practice to use a basic OBD2 scan tool to clear any stored DTCs after installation. This ensures the entire system recognizes the new, fully functional component.
Frequently Asked Questions
Why is VIN programming so important for this TCM?
VIN programming loads your vehicle’s specific software, including shift strategies, torque parameters, and communication protocols. Without it, the module won’t communicate correctly with your engine computer (ECM) and other systems, leading to continued shifting problems or a no-start condition. Our service saves you a trip to the dealer and ensures 100% correct functionality right out of the box.
Will this part fix a P0700 trouble code?
A P0700 code is a general fault code requested by the TCM. It means the TCM has detected a problem and has stored more specific codes. In many cases where the TCM itself is faulty, replacing it with our programmed module will resolve the root cause and allow you to clear the P0700 and related codes for good.
Where is the TCM located on a 2008 Chevy HHR?
For the 2006-2011 Chevrolet HHR, the Transmission Control Module is located in the engine compartment on the driver’s side, often near the strut tower or under the air cleaner box.
Is this a new or rebuilt part?
This is a high-quality, OEM-standard component that has been expertly prepared and programmed for your vehicle. It is inspected and verified to meet strict performance criteria and is backed by our comprehensive one-year warranty, ensuring reliability and peace of mind.
Do I need any special tools for installation?
No special tools are required. Basic hand tools, such as a socket set to disconnect the battery and unbolt the module, are all that’s needed for the physical installation. A simple OBD2 scanner is recommended to clear any stored codes after the job is complete.