Regain Control of Your 4WD System
If you’re dealing with a frustrating “Service 4WD” light, an inability to shift between 2WD and 4WD, or erratic four-wheel-drive behavior in your 2011-2014 Sierra Denali 3500, a failing Transfer Case Control Module (TCCM) is the most common culprit. This isn’t just an inconvenience; it’s a reliability issue that can leave you stranded in tough weather or off-road conditions. This direct-replacement TCCM, part number 24243085, is the definitive solution to restore your truck’s crucial all-terrain capabilities.
The biggest challenge with replacing a TCCM has always been the expensive and time-consuming trip to the dealership for programming. We eliminate that step entirely. By providing us with your vehicle’s VIN at checkout, you will receive a module that is professionally flashed with the latest GM-certified software. It arrives at your door ready for a straightforward, plug-and-play installation, saving you hundreds of dollars in dealer fees and hours of vehicle downtime.
A Technician’s Notebook: The Misleading Encoder Motor
A 2012 Sierra 2500HD came into my bay with the classic ‘Service 4WD’ light and no response from the selector switch. The initial codes pointed towards the transfer case encoder motor, a common failure point. The owner had already replaced it himself, but the problem persisted. Instead of throwing more parts at it, I checked the communication lines to the TCCM. The module was powered but completely unresponsive on the data bus—a tell-tale sign of internal failure. After installing a pre-programmed 2011-2014 Sierra Denali 3500 TCCM, the system immediately came back online, and all functions were restored. It’s a powerful reminder to always verify module communication before condemning more expensive mechanical parts.
Is Your Truck Showing These Symptoms?
A faulty TCCM can manifest in several ways. If you’re experiencing any of the following, this module is the likely fix you need:
- ✔ “Service 4WD” or “Service Four Wheel Drive” message on the instrument cluster.
- ✔ 4WD selector switch lights are off or flash without engaging.
- ✔ Vehicle is stuck in 2WD, 4HI, or 4LO.
- ✔ Grinding or clunking noises during attempted shifts of the transfer case.
- ✔ Diagnostic Trouble Codes (DTCs) such as C0306, C0327, C0374, or U0102 stored in the system.
- ✔ Inability to communicate with the TCCM using a professional scan tool.
A Straightforward Guide to Your TCCM Installation
Installing your new TCCM is a job most DIYers can handle in under 30 minutes with basic hand tools. Here’s how to get it done right:
- Safety First: Disconnect the negative terminal from your truck’s battery to prevent any electrical shorts.
- Locate the Module: The TCCM is typically located on the driver’s side, mounted to a bracket behind the lower dashboard panel, to the left of the steering column.
- Remove Trim Panels: Carefully remove the necessary lower dash panels to gain access to the module. Usually, this involves a few screws or clips.
- Unplug and Unbolt: Disconnect the electrical connectors from the old TCCM. They have locking tabs that need to be depressed. Then, remove the nuts or bolts holding the module to its mounting bracket.
- Install the New Module: Mount your new, pre-programmed TCCM onto the bracket and securely fasten it. Reconnect the electrical connectors, ensuring they click into place.
- Reassemble and Test: Reinstall the trim panels, reconnect the battery terminal, and start your truck. The “Service 4WD” light should be off. Test the 4WD selector switch to confirm proper operation between all modes.
Guaranteed Fitment for Your GM Truck or SUV
This module is a direct replacement for a wide range of GM vehicles. We guarantee compatibility if your vehicle is listed below. It replaces part numbers: 24261367, 12588096, 24239190, 24240487, 24241143, 24241970, 24242480, 24243084, 24243085, 24249095, 24252878.
- AVALANCHE 1500: 2008-2013
- SIERRA/SILVERADO 1500: 2007 (New Body Style), 2008-2013
- SIERRA/SILVERADO 2500 & 3500: 2007 (New Body Style), 2008-2014
- SIERRA DENALI: 2007-2010
- SIERRA DENALI 2500/3500: 2011-2014
- SUBURBAN 1500/2500: 2008-2014/2008-2013
- TAHOE & YUKON: 2007 (Denali), 2008-2014
- YUKON XL 1500/2500: 2007 (Denali), 2008-2014/2008-2013
Frequently Asked Questions
Frequently Asked Questions
Why do you need my VIN?
Your Vehicle Identification Number (VIN) allows us to flash the module with the exact software and calibrations specified by GM for your truck’s specific options. This ensures perfect compatibility and function without any additional programming required.
Is this a difficult part to install myself?
Not at all. For most DIYers with basic tools, this is a simple, plug-and-play installation that takes less than an hour. Our guide above outlines the straightforward process.
Will this fix the ‘Service 4WD’ light?
In the vast majority of cases, yes. A failed TCCM is the most common reason for the ‘Service 4WD’ light and related shifting issues on these GM trucks. This pre-programmed module is designed to be the definitive fix for that problem.
What if I have a different part number on my old module?
Our module is a direct replacement for a wide range of original part numbers, including 24243084, 24252878, and many others listed above. As long as your vehicle model and year are on our compatibility list, this module will work perfectly.