Restore Your Chevy HHR’s Shifting Performance
If you’re dealing with the frustration of a Chevrolet HHR that shifts erratically, gets stuck in gear, or has an illuminated Check Engine Light, a failing Transmission Control Module (TCM) is the most likely culprit. As a technician with over two decades of experience, I’ve seen how a faulty TCM can make a reliable car feel unpredictable and unsafe. This isn’t just an annoyance; it’s a critical failure that impacts drivability and fuel economy. This OEM-quality T42 TCM, part number 24235753, is the definitive solution, arriving pre-programmed to your vehicle’s VIN for a true plug-and-play repair.
Is Your HHR Showing These Transmission Warning Signs?
A failing TCM doesn’t always mean a complete transmission breakdown. Often, it starts with subtle electrical glitches that cause major mechanical symptoms. Before you condemn the entire transmission, check if you’re experiencing any of these common issues, which often point directly to the module.
- ✔ Harsh, banging shifts or delayed gear engagement from a stop.
- ✔ The vehicle is stuck in a single gear, often called “limp mode,” making it difficult to accelerate.
- ✔ An active Check Engine Light or transmission warning light, with Diagnostic Trouble Codes (DTCs) like P0700 (Transmission Control System Malfunction), P0750-P0758 (Solenoid Faults), or other communication errors.
- ✔ Inability to upshift or downshift, leading to poor acceleration and terrible gas mileage.
- ✔ The transmission seems to slip between gears, causing the engine to rev without a corresponding increase in speed.
Case Study: A Tricky Diagnosis
A customer brought in their 2009 HHR with an intermittent no-shift condition. It would drive fine for days, then suddenly refuse to shift out of 2nd gear. They had already replaced two shift solenoids at another shop with no success. After hooking up my scan tool, I noticed the TCM would intermittently lose communication. A visual inspection revealed no wiring damage. In my experience, these T42 modules, especially after years of heat cycles in the engine bay, can develop internal circuit board failures. We installed one of our VIN-programmed TCMs, and the problem was solved instantly. The customer saved hundreds by avoiding an unnecessary transmission rebuild.
The Smart Solution: A Pre-Programmed 2006-2011 HHR TCM
Why is our module the best choice for your repair? It’s all about eliminating the extra steps and costs. Dealerships will sell you a blank module, requiring you to have the vehicle towed in for expensive programming. Our service handles that for you. We flash the module with the latest GM software updates specific to your HHR’s VIN. When it arrives, it’s ready to install right out of the box, restoring the precise shift logic, torque converter lockup strategy, and diagnostic functions your vehicle was designed with.
A Straightforward Guide to Installation
For the confident DIYer or professional mechanic, replacing the TCM on an HHR is a simple job that typically takes less than 30 minutes. The module is conveniently located and requires only basic hand tools.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent electrical shorts and help reset the system.
- Locate the TCM: On the 2006-2011 HHR, the Transmission Control Module is typically found in the engine compartment, mounted to the left-hand (driver’s side) inner fender or strut tower area.
- Disconnect and Remove: Carefully unclip the electrical connectors. Be gentle with the locking tabs, as old plastic can be brittle. Then, unbolt the module from its mounting bracket.
- Install the New Module: Bolt the new, pre-programmed TCM into place and securely reconnect the electrical harnesses. You should hear a ‘click’ as they lock.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s always best practice to use a standard OBD2 scan tool to clear any stored fault codes from the system’s memory. Start the vehicle and take it for a test drive to confirm smooth shifting.
Verified Compatibility for Your Vehicle
This T42 Transmission Control Module is a direct replacement for part number 24235753 and is interchangeable with a wide range of other GM service numbers. It is guaranteed to fit the following models and configurations:
- Chevrolet HHR: 2006, 2007, 2008, 2009, 2010, 2011 (Located in LH engine compartment)
- Chevrolet Cobalt: 2006-2010 (Located on LH strut tower)
- Pontiac G5 / G6: 2006-2010 (Located on LH strut tower)
- Saturn Ion: 2006-2007 (Located behind LH strut tower)
- This module also fits a wide variety of other GM cars, trucks, and SUVs from 2006-2014. Please verify your part number or contact us with your VIN to ensure perfect fitment.
Frequently Asked Questions
Do I need to get this module programmed by a dealer?
No. This is the biggest benefit of our service. We pre-program the module to your vehicle’s specific VIN before shipping. It arrives ready for installation, saving you time and the high cost of dealership programming.
Is this a new or used part?
This is a high-quality, OEM-standard replacement part, rigorously tested to meet or exceed original performance specifications and backed by our warranty.
Where is the TCM located on my 2007 Chevy HHR?
On the 2006-2011 Chevrolet HHR, the TCM is located in the engine bay, typically mounted on the driver’s side (LH) engine compartment wall or near the strut tower.
Will this fix a P0700 trouble code?
A P0700 code indicates a general fault request from the TCM. In many cases where the TCM itself has failed internally, replacing it with this programmed module will resolve the P0700 code and any related transmission-specific codes. However, you should always ensure the underlying issue isn’t a wiring or solenoid problem.
Is there a core charge?
No, there is no core charge for this part. You can keep or dispose of your old module without the hassle of returning it.