Restore Flawless Shifting to Your Chevrolet HHR
If you’re dealing with the frustrating and often unpredictable behavior of a failing transmission control module (TCM) in your 2006-2011 Chevy HHR, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen firsthand how a faulty TCM can make a perfectly good car feel unreliable. From harsh, slamming shifts to getting stuck in limp mode, the symptoms can be alarming. This T42 Transmission Control Module, corresponding to part number 24240400, is the definitive solution to restore your vehicle’s transmission to its original, smooth-operating condition.
The TCM is the brain of your automatic transmission. It processes data from various sensors to control shift timing, torque converter clutch engagement, and line pressure. When it fails, communication breaks down, leading to the issues you’re likely experiencing. Our modules are meticulously prepared and programmed to your vehicle’s specific VIN, eliminating the need for an expensive and time-consuming trip to the dealership. This isn’t just a replacement part; it’s a direct, plug-and-play fix that gets you back on the road with confidence.
From the Diagnostic Bay: The Misleading Solenoid Code
I remember a 2009 HHR that came into my shop stuck in 3rd gear with a check engine light on. The owner had already been quoted for a costly shift solenoid replacement by another shop based on a P0752 (Shift Solenoid ‘A’ Stuck On) code. However, after 20 years of diagnostics, you learn to look deeper. I checked the live data and saw erratic voltage readings from the TCM. We installed one of our VIN-programmed modules, cleared the codes, and the car shifted perfectly. The solenoid was fine; the TCM was sending bad signals. This is a classic case where replacing the brain, not the muscle, saves the customer hundreds of dollars and prevents unnecessary repairs.
Is Your HHR Showing These Telltale Signs?
A failing TCM often broadcasts its issues through clear symptoms. If your vehicle is exhibiting any of the following, a faulty module is the most likely culprit:
- ✔ Abrupt, harsh, or delayed gear shifts.
- ✔ Vehicle is stuck in one gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, especially P0700, P0750-P0758, or other solenoid-related codes.
- ✔ Failure to upshift or downshift correctly.
- ✔ Noticeable decrease in fuel economy.
- ✔ Intermittent loss of communication with the transmission.
A Straightforward Guide to Your HHR TCM Installation
One of the best features of this part is its simple installation, which most DIYers can complete in under 30 minutes. For the 2006-2011 HHR, the TCM is conveniently located in the engine compartment. Follow these steps for a smooth replacement:
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electronic work.
- Locate the Module: On the HHR, you’ll find the TCM in the left-hand (driver’s side) of the engine compartment, often near the strut tower. It’s a silver box with electrical connectors.
- Disconnect and Remove: Carefully unplug the wiring harness connectors. Then, unbolt the module from its mounting bracket.
- Install the New TCM: Mount your new, pre-programmed module in the same location and securely fasten the bolts. Reconnect the wiring harnesses, ensuring they click into place.
- Final Steps: Reconnect the battery terminal. While the module is plug-and-play, it’s good practice to use a basic OBD2 scanner to clear any stored fault codes from the vehicle’s memory.
Verified Vehicle Compatibility List
This T42 TCM is a direct fit for a wide range of General Motors vehicles. While this page focuses on the HHR, it is also compatible with the following models and more. Always verify your part number (24240400) or contact us with your VIN.
- Chevrolet HHR: 2006-2011 (LH engine compartment)
- Chevrolet Cobalt: 2006-2010 (LH strut tower)
- Pontiac G5 / G6: 2006-2010 (LH strut tower)
- Saturn Ion: 2006-2007 (Behind LH strut tower)
- Chevrolet Malibu: 2006-2010 (LH frame rail)
- Saturn Vue: 2007-2010 (2.4L, LH front engine compartment)
Don’t let a faulty module dictate how your car drives. Take control of your repair with this reliable, VIN-programmed solution and enjoy the peace of mind that comes with a smooth, predictable transmission.
Frequently Asked Questions
Do I need to have this TCM programmed by a dealer?
No. We program the module to your vehicle’s VIN before shipping. It arrives ready for plug-and-play installation, with no additional programming or dealer visits required.
What is the warranty on this part?
This transmission control module comes with a one-year warranty, covering any defects in materials or workmanship for your peace of mind.
Is there a core charge for my old part?
No, there is no core charge. You can keep your old part or recycle it locally without the hassle of shipping it back to us.
Where is the TCM located on my 2008 Chevy HHR?
On the 2006-2011 Chevrolet HHR, the TCM is located in the engine bay, on the driver’s side, typically mounted near the strut tower.
Will this fix a P0700 trouble code?
A P0700 code is a general fault request from the TCM to the main engine computer (ECM). While this module often resolves the underlying issue causing the P0700, it’s crucial to scan for more specific transmission codes (like P07xx) to confirm the diagnosis. A faulty TCM is a very common cause.