Fix Your HHR’s Shifting Problems for Good
If you’re dealing with a 2006-2011 Chevrolet HHR that’s shifting harshly, getting stuck in gear, or throwing transmission codes, the culprit is very likely a failing Transmission Control Module (TCM). As a technician with over two decades of experience, I’ve seen these T42 modules cause headaches for countless owners. The electronics inside can degrade from heat and vibration, leading to unpredictable and unsafe driving conditions. This isn’t just an annoyance; it’s a critical failure that compromises your vehicle’s reliability.
This replacement TCM, part number 24240400, is the definitive solution. We take the guesswork and high cost out of the repair by pre-programming the module to your HHR’s specific Vehicle Identification Number (VIN). This means it’s a true plug-and-play part. You won’t need a trip to the dealership for expensive programming—a step that can often cost as much as the part itself. This is the same process we use in the shop to guarantee a fast, effective repair that gets our customers back on the road safely.
A Technician’s Notebook: The Intermittent HHR Shifter
A customer brought in their 2009 HHR with a frustrating problem: it would occasionally refuse to shift out of 2nd gear, but only after driving for 20-30 minutes. The check engine light was on, but the codes were intermittent. After checking the wiring and solenoids, which all tested fine, we suspected the TCM. Heat soak was causing an internal fault in the module that only appeared when the engine bay got hot. Instead of a lengthy and expensive diagnostic process, we installed a VIN-programmed TCM. The problem was solved instantly, saving the customer hundreds in diagnostic labor and providing a permanent fix.
Is Your HHR Exhibiting These Transmission Faults?
A failing 2006-2011 HHR TCM will make its presence known. Watch for these common indicators that it’s time for a replacement:
- ✔ Sudden, harsh, or delayed gear shifts.
- ✔ Vehicle is stuck in a single gear (often called “limp mode”).
- ✔ Check Engine Light or Transmission Warning Light is illuminated.
- ✔ Diagnostic Trouble Codes (DTCs) are present, such as the general code P0700 or specific solenoid codes like P0750, P0753, P0758.
- ✔ Complete loss of communication with the TCM (no-start or no-shift condition).
- ✔ Poor fuel economy and a feeling of sluggish performance.
A Straightforward Guide to Your HHR TCM Installation
One of the best features of this part is its simple installation. You can get this job done in your own garage in under 30 minutes with basic hand tools. For the Chevy HHR, the TCM is typically easy to access.
- Safety First: Disconnect the negative terminal from your vehicle’s battery to prevent any electrical shorts and to help reset the system.
- Locate the Module: On the 2006-2011 HHR, the TCM is found in the engine compartment, usually mounted to the left-hand (driver’s side) inner fender or strut tower area.
- Disconnect and Remove: Carefully unplug the electrical connectors. They have locking tabs that need to be released. Once disconnected, unbolt the old module from its mounting bracket.
- Install the New TCM: Bolt the new, VIN-programmed TCM into place. Reconnect the electrical harnesses, ensuring they click securely into position.
- Final Steps: Reconnect the battery terminal. While our programming handles the critical setup, it’s always a good practice to use a basic OBD2 scan tool to clear any lingering fault codes from the vehicle’s memory. Start the vehicle and enjoy smooth shifting!
Verified Vehicle Compatibility
While this page focuses on the 2006-2011 HHR TCM, this T42 module is compatible with a wide array of General Motors vehicles. Please verify your part number (24240400 or an interchange number) and vehicle model from the list below to ensure a perfect fit.
- ALLURE 06-09
- AVALANCHE 1500 07-08
- CANYON 08-12
- COBALT 06-10
- COLORADO 08-12
- DTS 06-11
- ENVOY 06-09
- EXPRESS 1500/2500/3500 VAN 06-14
- G5 07-10
- G6 06-10
- GRAND PRIX 06-08
- HHR 06-11
- HUMMER H3 08-10
- IMPALA 06-11
- ION 06-07
- LACROSSE 06-09
- LUCERNE 06-11
- MALIBU 06-10
- MONTE CARLO 06-07
- MONTANA 06-09
- PURSUIT 06
- RAINIER 06-07
- RENDEZVOUS 06-07
- SAAB 9-7X 06-09
- SAVANA 1500/2500/3500 VAN 06-14
- SIERRA 1500/2500 PICKUP 07-13
- SILVERADO 1500/2500 PICKUP 07-13
- SSR 05-06
- SUBURBAN 1500 07-08
- TAHOE 07-09
- TERRAZA 06-07
- TRAILBLAZER 06-09
- UPLANDER 06-09
- VUE 07-10
- YUKON & YUKON XL 1500 07-09
What does ‘VIN Programmed’ actually mean?
What does ‘VIN Programmed’ actually mean?
It means we load your vehicle’s unique 17-digit VIN into the module before shipping. This ensures the TCM has the correct software and calibration files specifically for your HHR’s transmission and options. It makes the part ready for installation right out of the box, with no additional dealer tools required.
Do I have to send my old TCM back (core charge)?
No, there is absolutely no core charge or need to return your old part. You can dispose of it or keep it without any hassle.
Will this programmed 2006-2011 HHR TCM fix a P0700 trouble code?
In many cases, yes. A P0700 code is a general fault request from the TCM to the main engine computer (ECM) to turn on the check engine light. If the underlying cause is an internal failure of the TCM, replacing it with this programmed unit will resolve the root problem and allow the code to be cleared permanently.
Is this an OEM part?
This is a high-quality replacement part built to meet or exceed original equipment manufacturer (OEM) standards for performance and reliability. It is programmed with the latest official GM software updates for your vehicle, ensuring optimal function.