Restore Peak Performance to Your GM Truck’s Transmission
Is your 2019-2020 Sierra Denali 1500 suffering from erratic shifting, delayed engagement, or an illuminated “Service Transmission” light? These are classic signs of a failing Transmission Control Module (TCM). As a seasoned technician, I’ve seen these issues sideline even the toughest trucks. This isn’t just an annoyance; it’s a critical failure that compromises your vehicle’s performance and reliability. This replacement TCM, part number 24289415, is the definitive solution to get your truck operating smoothly and dependably again.
The biggest hurdle in replacing a modern TCM is the complex programming required. We eliminate that obstacle completely. Before this module ships, we flash it with the latest official GM software, calibrated specifically to your truck’s Vehicle Identification Number (VIN). This means it arrives at your door ready for installation, with no need for expensive dealership trips or specialized scan tools. It’s a direct-fit, plug-and-play solution designed to save you time, money, and frustration.
From the Diagnostic Bay: The Limp Mode Mystery
A customer brought in his 2019 Silverado 1500 (which uses the same platform as the Sierra) stuck in limp mode. It would barely shift out of third gear, and the dash was lit up with warnings. He was worried about a complete transmission rebuild. After connecting my scanner, I pulled codes U0101 (Lost Communication with TCM) and P0752 (Shift Solenoid ‘A’ Stuck On). While the P-code pointed to a solenoid, the U-code was the real culprit. In my experience, communication loss codes often indicate the module itself is the point of failure, not the internal components it controls. We replaced the original module with a pre-programmed Sierra Denali 1500 TCM like this one. The installation took less than an hour, and upon startup, all codes were clear. The truck shifted perfectly on the test drive. The customer saved thousands by avoiding an unnecessary transmission teardown, all thanks to a correct diagnosis and a properly prepared module.
Is Your Truck Exhibiting These Transmission Faults?
A failing TCM can manifest in several ways. If you’re experiencing any of the following, this module is the likely solution:
- ✔ Harsh, jerky, or delayed shifting
- ✔ Vehicle getting stuck in one gear (limp mode)
- ✔ “Service Transmission” or Check Engine Light illuminated
- ✔ Inaccurate gear indicator on the dashboard
- ✔ Common Diagnostic Trouble Codes (DTCs) such as P0700, P0751, P0752, U0100, or U0101
- ✔ Complete loss of gear engagement
A Straightforward Guide to Installation
Installing your new Sierra Denali 1500 TCM 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 behind the headlight.
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Locate the Module: Find the TCM mounted to the left-hand (driver’s side) core support in the engine bay.
- Disconnect Connectors: Carefully release the locking tabs and unplug the main electrical harnesses from the old TCM. Inspect the connectors for any corrosion or damage.
- Remove Old Module: Unbolt the old TCM from its mounting bracket. There are typically a few small bolts holding it in place.
- Install New Module: Mount your new, pre-programmed TCM onto the bracket and secure the bolts.
- Reconnect and Secure: Plug the electrical harnesses firmly into the new module until they click, ensuring a secure connection.
- Final Step: Reconnect the negative battery terminal. In some cases, a transmission adaptive pressure relearn procedure may be recommended with a capable scan tool for optimal performance, but the truck should be fully operational.
Verified Vehicle Compatibility
This module is a direct replacement for service number 24042698 and others, ensuring precise fit and function for a wide range of GM vehicles. Please confirm your model and year from the list below. We program the module based on the VIN you provide, guaranteeing compatibility.
CAMARO 22-23 Transmission Control; (underhood, LH frame rail)
SIERRA 1500 PICKUP 19 Transmission Control; new style (mirrors mount on door skin), (LH core support)
SIERRA 1500 PICKUP 20 Transmission Control; (LH core support)
SIERRA 2500 PICKUP 20-22 Transmission Control; (LH core support)
SIERRA 3500 PICKUP 20-22 Transmission Control; (LH core support)
SIERRA DENALI 1500 19-20 Transmission Control; (LH core support)
SIERRA DENALI 2500 20-22 Transmission Control; (LH core support)
SIERRA DENALI 3500 20-22 Transmission Control; (LH core support)
SILVERADO 1500 PICKUP 19 Transmission Control; new style (mirrors mount on door skin), (LH core support)
SILVERADO 1500 PICKUP 20 Transmission Control; (LH core support)
SILVERADO 2500 PICKUP 20-21 Transmission Control; (LH core support)
SILVERADO 3500 PICKUP 20-21 Transmission Control; (LH core support)
This part is a direct replacement for the following service numbers: 24042698, 24043411, 24043413, 24289415, 24296206.
Frequently Asked Questions
Frequently Asked Questions
How does the programming process work?
After you complete your purchase, you must provide us with your vehicle’s 17-digit VIN. Our technicians will then use this VIN to load the latest, correct GM software onto the module before shipping it to you.
Is this part difficult to install myself?
For someone with basic mechanical skills and tools, the installation is straightforward. The module is accessible in the engine bay, and the process involves unplugging connectors and unbolting the old unit. Please see our installation guide above.
Will this fix my truck’s hard shifting problem?
Yes, a faulty TCM is one of the most common causes of hard shifting, delayed engagement, and limp mode in these trucks. This pre-programmed Sierra Denali 1500 TCM is designed to resolve those specific issues.
Do I need to have the dealership do anything after installation?
No. Because we program the module to your VIN before shipment, you do not need to visit a dealer for programming. It is designed to be a plug-and-play solution.
What happens if I don’t provide my VIN?
We cannot ship the module without your VIN. The programming is essential for the part to function correctly in your vehicle. We will contact you after your purchase to request the VIN if it was not provided.