Is Your Hummer H3 Experiencing Transmission Problems?
If you’re dealing with erratic shifting, a check engine light that won’t go away, or your 2008-2010 Hummer H3 is stuck in limp mode, a faulty Transmission Control Module (TCM) is the likely culprit. The TCM is the electronic brain of your automatic transmission, responsible for orchestrating every gear change, managing torque converter lockup, and ensuring smooth, efficient operation. When it fails, it can make your rugged H3 feel unpredictable and unsafe to drive. This genuine GM T42 TCM, service part number 24252114, is the definitive solution to restore your vehicle’s factory performance and reliability.
From the Diagnostic Bay
We recently had a 2009 H3 come into the shop that the owner was about to give up on. It was randomly slamming into gear and sometimes wouldn’t shift past 2nd. The local dealer quoted him an astronomical price for a new module plus programming fees. We scanned it and found multiple solenoid circuit codes, a classic sign of internal TCM failure. We installed one of our VIN-programmed T42 modules, cleared the codes, and the H3 was shifting perfectly on the test drive. The customer was thrilled to have his truck back without the dealership hassle and expense. This isn’t just a part; it’s a complete, straightforward fix.
Diagnosing a Failing Hummer H3 Transmission Module
A failing TCM can manifest in various ways, often mimicking mechanical transmission failure. Before considering a costly transmission rebuild, check for these common electronic symptoms. A faulty Hummer H3 Transmission Module will often trigger specific diagnostic trouble codes (DTCs) and noticeable performance issues. This replacement part is engineered to resolve these exact problems.
Symptoms of a Bad TCM
- ✔ Harsh, delayed, or erratic gear shifts that make driving uncomfortable.
- ✔ The vehicle gets stuck in a single gear, often referred to as “limp mode,” to prevent further damage.
- ✔ An illuminated Check Engine Light or Transmission Warning Light on your dashboard.
- ✔ Diagnostic trouble codes such as P0700 (Transmission Control System Malfunction) or various solenoid-specific codes (e.g., P0750, P0753).
- ✔ Inability to upshift or downshift, leading to poor acceleration and high RPMs.
- ✔ A noticeable decrease in fuel economy as the transmission operates inefficiently.
- ✔ Complete loss of communication with the module, resulting in a no-start or no-shift condition.
Plug-and-Play Solution with VIN Programming
The biggest challenge when replacing modern vehicle electronics is the need for expensive dealership programming. We eliminate this step entirely. Each module is pre-programmed to your Hummer H3’s specific Vehicle Identification Number (VIN) before it ships. This ensures that the TCM has the latest GM software and is perfectly calibrated for your vehicle’s configuration. The result is a true plug-and-play installation that restores communication between the engine and transmission for optimal performance right out of the box.
This T42 TCM is a direct replacement for a wide range of GM vehicles equipped with 4-speed automatic transmissions like the 4L60E, 4L65E, and 4L70E. It is interchangeable with numerous part numbers, including 24234503, 24230461, 24242391, and 24256960, making it a versatile and reliable choice for your repair.
Easy Installation Process
For the 2008-2010 Hummer H3, the TCM is located in the engine compartment on the right-hand rear side. The replacement process is straightforward for a DIY mechanic or any professional technician. Simply disconnect the battery, unplug the electrical connectors from the old module, unbolt it, and install the new one in its place. Reconnect everything, and you’re ready to go. We recommend using a basic scan tool to clear any stored DTCs after installation is complete. Best of all, there is no core charge, so you don’t have to worry about the cost and hassle of returning your old part.
Will this TCM fit my vehicle?
This module is a direct fit for 2008, 2009, and 2010 Hummer H3 models. It is also compatible with a wide range of other GM vehicles from 2006-2014. Please verify your part number or contact us with your VIN to confirm compatibility.
Is any additional programming required after installation?
No. This Transmission Control Module comes pre-programmed to your vehicle’s VIN. It is ready for immediate installation without the need for a trip to the dealership or any special programming tools.
Where is the TCM located on my Hummer H3?
On the 2008-2010 Hummer H3, the TCM is typically found in the engine compartment, on the right-hand (passenger side) rear area. Always disconnect the vehicle’s battery before starting the replacement.
What is the warranty on this part?
This part comes with a one-year warranty, ensuring it is free from defects and providing you with peace of mind for your repair.
Do I need to return my old TCM?
No, there is no core charge for this module. You can keep your old part without any additional fees or hassle.