If your 2019-2020 Sierra Denali 1500 is suffering from harsh shifts, getting stuck in gear, or throwing transmission-related codes, you’ve come to the right place. As a technician with over two decades of experience, I’ve seen firsthand how a failing Transmission Control Module (TCM) can bring a powerful truck to a standstill. The constant worry about whether your transmission will cooperate is frustrating and can be unsafe. This isn’t just a part; it’s the solution to restore your truck’s performance and your peace of mind.
This is a genuine GM Transmission Control Module, part number 24289415, which is the direct replacement for service numbers 24042698, 24043411, 24043413, 24296206, and more. The most significant benefit we offer is that this module arrives at your doorstep fully programmed to your truck’s specific VIN. We flash it with the latest, most stable software from GM before it ships. This means you can bypass the expensive and time-consuming trip to the dealership for programming. It’s a plug-and-play solution designed for a straightforward installation.
Is Your Truck Exhibiting These TCM Failure Symptoms?
- ✔ Unpredictable or harsh shifting between gears
- ✔ The transmission feels like it’s slipping or hesitating
- ✔ Your truck gets stuck in one gear (limp mode)
- ✔ The Check Engine Light is illuminated
- ✔ Common Diagnostic Trouble Codes (DTCs) stored, such as P0700 (Transmission Control System Malfunction) or U0101 (Lost Communication with TCM)
- ✔ Delayed engagement when shifting from Park to Drive or Reverse
Case Study: A Tricky Diagnosis
I had a 2019 Silverado 1500 in the bay last month with a classic complaint: ‘It just doesn’t shift right.’ The customer had already replaced a speed sensor with no luck. A quick scan showed a U0101 code—lost communication with the TCM. While this can sometimes be a wiring issue, on these newer GM trucks, the TCM itself is a common culprit. We checked the power and ground feeds at the module connector, and they were solid. That confirmed the internal failure of the original TCM. We installed a VIN-programmed module, performed the transmission service relearn procedure, and the truck was shifting like new. This pre-programmed unit saves you that diagnostic headache.
Installing Your 2019-2020 Sierra Denali TCM
Replacing the TCM on these trucks is a manageable job for a confident DIYer or any professional mechanic. The module is typically located on the driver’s side (LH) core support, near the radiator. With this pre-programmed unit, you eliminate the most complex step.
- Safety First: Always disconnect the negative terminal from your truck’s battery before beginning any electrical work.
- Locate the TCM: On most 2019+ Sierra/Silverado models, you’ll find the TCM mounted to a bracket on the left-hand (driver’s side) core support in the engine bay.
- Disconnect Electrical Connectors: Carefully release the locking tabs on the electrical harnesses and pull them straight out from the module. Do not force them. Inspect the connectors for any signs of corrosion or damage.
- Remove the Old Module: Unbolt the TCM from its mounting bracket. It’s typically held in place by a few small bolts.
- Install the New Module: Mount your new, pre-programmed TCM onto the bracket and secure it with the bolts. Reconnect the electrical connectors, ensuring they click securely into place.
- Reconnect the Battery: Reattach the negative battery terminal. While the module is programmed, it’s best practice to perform a transmission service relearn procedure with a capable scan tool to ensure the smoothest operation from the start.
Guaranteed Fitment for Your GM Vehicle
This module is verified to fit the following vehicles. Please confirm your model and year to ensure compatibility. Remember to provide your VIN upon purchase for programming.
- ✔ CAMARO: 2022-2023
- ✔ SIERRA 1500 PICKUP: 2019 (New Style), 2020
- ✔ SIERRA 2500 PICKUP: 2020-2022
- ✔ SIERRA 3500 PICKUP: 2020-2022
- ✔ SIERRA DENALI 1500: 2019-2020
- ✔ SIERRA DENALI 2500: 2020-2022
- ✔ SIERRA DENALI 3500: 2020-2022
- ✔ SILVERADO 1500 PICKUP: 2019 (New Style), 2020
- ✔ SILVERADO 2500 PICKUP: 2020-2021
- ✔ SILVERADO 3500 PICKUP: 2020-2021
Frequently Asked Questions
Why do you need my VIN?
Your truck’s Vehicle Identification Number (VIN) is essential. We use it to load the exact, correct GM factory software for your vehicle’s specific configuration (engine, transmission, axle ratio, etc.). This ensures the module works perfectly right out of the box.
Is this part difficult to install?
The physical installation is straightforward for anyone with basic mechanical skills. It involves disconnecting the battery, unplugging connectors, and unbolting the old module. Since our module is pre-programmed, you avoid the need for specialized dealer software, which is the hardest part of the job.
Will this fix my ‘Service Transmission’ light?
If the light is caused by a faulty TCM or related communication codes (like U0101), this part is the correct solution. It’s crucial to properly diagnose the issue, but a failing TCM is a very common cause for this warning on these trucks.
Is this a new or used part?
This is a genuine, high-quality replacement part that has been programmed with the latest vehicle-specific software from GM. It meets or exceeds original equipment specifications for a reliable, long-term repair.
What if I have questions during installation?
We’re a team of experienced automotive professionals. While we can’t be there in person, we are happy to provide guidance and answer questions to help you get the job done right. Your success is our priority.