Experiencing erratic shifting, a flashing check engine light, or a “Service Transmission” message on your dash? A failing Transmission Control Module (TCM) is one of the most common culprits on modern GM trucks, turning a dependable workhorse into an unpredictable source of frustration. In my 20+ years as a technician, I’ve seen how a faulty TCM can sideline a vehicle, causing everything from harsh gear engagement to a complete no-shift condition. This isn’t just an inconvenience; it’s a critical failure that compromises your truck’s performance and your confidence on the road.
We offer a direct, reliable solution. This is a genuine GM Transmission Control Module, service part number 24289415, which replaces a range of original service numbers including 24042698. The most significant benefit we provide is our professional programming service. Before this module ships, we flash it with the latest GM-approved software, specifically matched to your truck’s Vehicle Identification Number (VIN). This eliminates the need for an expensive trip to the dealership for programming, making this a true plug-and-play fix for both professional shops and capable DIYers.
Is Your Truck Exhibiting These Telltale Signs?
- ✔ Harsh or delayed shifting between gears
- ✔ Getting stuck in one gear (limp mode)
- ✔ “Service Transmission” or “Shift to Park” warnings
- ✔ Check Engine Light with transmission-related Diagnostic Trouble Codes (DTCs)
- ✔ Common codes include P0700 (Transmission Control System Malfunction), U0100 (Lost Communication With TCM), or other U-codes indicating a communication fault.
- ✔ Inability to shift out of Park
From the Diagnostic Bay
I recently had a 2019 Sierra 1500 in the shop with a classic, tricky TCM issue. The customer complained of intermittent harsh downshifts and a random “Service Transmission” light that would disappear on its own. A quick scan showed a stored U0100 code. While this points to the TCM, it can also be caused by a bad wire or a corroded connector pin at the module. We checked the harness and found it pristine. The real confirmation came from monitoring live data—the TCM would momentarily drop offline, causing the symptom. Replacing it with a pre-programmed module like this one resolved the issue instantly. It’s a reminder that while wiring should always be checked, these modules are a known failure point, and a quality replacement is the definitive fix.
A Straightforward Guide to Installation
Replacing the 2019-2020 Silverado 1500 TCM is a manageable job for those with basic mechanical skills. Since we handle the programming, you won’t need any special scan tools for setup.
- Safety First: Always disconnect the negative terminal from your vehicle’s battery before starting any electrical work.
- Locate the TCM: On most 2019+ Silverado and Sierra models, the TCM is mounted on the driver’s side (LH) core support, near the front of the engine bay. On some models like the Camaro, it’s on the LH frame rail.
- Disconnect Connectors: Carefully release the locking tabs and unplug the electrical connectors from the old TCM. Inspect them for any signs of corrosion or damage.
- Unbolt the Module: Remove the mounting bolts or nuts holding the old module to its bracket.
- Install the New TCM: Mount your new, pre-programmed TCM in the same location, securing it with the original hardware.
- Reconnect and Finalize: Plug the electrical connectors firmly into the new module until they click. Reconnect the negative battery terminal. The vehicle may require a brief drive cycle for the transmission to complete its relearn process for optimal shift quality.
Verified Vehicle Compatibility
This module is a direct-fit replacement for the following vehicles, provided the service number matches. Please ensure your vehicle is on this list before ordering.
- CAMARO 2022-2023 (underhood, LH frame rail)
- SIERRA 1500 PICKUP 2019 (new style, mirrors on door skin), 2020 (LH core support)
- SIERRA 2500/3500 PICKUP 2020-2022 (LH core support)
- SIERRA DENALI 1500 2019-2020 (LH core support)
- SIERRA DENALI 2500/3500 2020-2022 (LH core support)
- SILVERADO 1500 PICKUP 2019 (new style, mirrors on door skin), 2020 (LH core support)
- SILVERADO 2500/3500 PICKUP 2020-2021 (LH core support)
Frequently Asked Questions
Do I need to do any programming after I receive this TCM?
No. We program the module to your vehicle’s specific VIN before shipping it. This makes the installation process much simpler, as you will not need a trip to the dealer for software flashing.
How do I provide my VIN?
After you complete your purchase, you will need to send us your 17-digit Vehicle Identification Number (VIN). We cannot ship the part until we receive this information, as it is essential for correct programming.
What is a service number?
Automakers often use multiple part numbers (service numbers) for the same component over its production life. This module, part number 24289415, is the correct replacement for all the service numbers listed, including 24042698, 24043411, and others.
Is this a difficult part to install myself?
For someone with basic automotive experience, it is a relatively simple replacement. The module is typically easy to access in the engine bay, requiring only basic hand tools to unbolt and disconnect. The most complex part—programming—is already done for you.
Will this fix my truck’s hard shifting problem?
A faulty TCM is a very common cause of harsh shifting, limp mode, and transmission error codes. While other issues can cause similar symptoms (like bad solenoids or wiring), replacing a known-faulty TCM with this pre-programmed unit is the correct solution for a module failure.