OEM Telematics Control Module for 2020-2024 Buick, Cadillac, Chevrolet, & GMC

What to look for:

• Correct Part: Make sure the part is designed for your specific year, make, and model.
• Condition: If buying used, check for physical damage, corrosion, or signs of tampering.
• Warranty: Look for a warranty to protect against defects or premature failure.

Quality Indicators:

• OEM Markings: Original Equipment Manufacturer (OEM) parts will have the manufacturer's logo and part number.
• Testing: Used parts should be tested and verified to be in working condition.
• Reputation: Buy from a reputable seller with positive reviews and a good return policy.

What's Included:

• The Telematics Control Module itself.
• Mounting hardware may or may not be included. Check with the seller.
• Programming instructions may be needed and are typically NOT included.

Difficulty Level: Medium

Estimated Time: 1-2 hours

Special Tools Needed:

• Basic hand tools (sockets, wrenches, screwdrivers)
• Scan tool for clearing diagnostic trouble codes (DTCs)
• Possibly a programming tool to configure the new module to your vehicle (check with your mechanic)

Critical Steps and Tips:

1. Disconnect the negative battery cable before starting.
2. Locate the Telematics Control Module (usually under the dash or in the trunk).
3. Disconnect the wiring connectors and remove the old module.
4. Install the new module and reconnect the wiring connectors.
5. Reconnect the negative battery cable.
6. Use a scan tool to clear any DTCs.
7. You may need to have the new module programmed to your vehicle by a qualified technician.

DIY or Professional Installation:

• Replacing the module itself is relatively straightforward.
• However, programming the new module often requires specialized equipment and knowledge.
• Professional installation is recommended to ensure proper programming and functionality.

• Used OEM: Original equipment from the factory, tested and inspected. Offers great value.
• New Aftermarket: Brand new parts manufactured by third-party companies to meet OE specifications.

Used OEM:

• Pros: Genuine factory part, lower cost than new, typically reliable.
• Cons: May have some wear and tear, limited warranty.

New Aftermarket:

• Pros: Brand new, readily available, often comes with a warranty.
• Cons: Quality can vary, may not be identical to the original part.

• Battery: A weak or failing battery can cause communication problems with the telematics system.
• Wiring Harness: Damaged or corroded wiring can disrupt the signal to the module.
• Antenna: The telematics antenna is needed for cellular and GPS connectivity.

Replacing related parts can prevent repeat failures by addressing underlying issues that may have contributed to the original module's failure. For example, replacing a corroded wiring harness can prevent future electrical problems.

• The Telematics Control Module typically lasts 7-10 years.

Factors that affect longevity:

• Climate: Extreme temperatures and humidity can shorten the lifespan of electronic components.
• Driving Conditions: Rough roads and constant vibration can cause premature failure.
• Maintenance: Keeping the vehicle properly maintained can help prevent electrical problems that can damage the module.
• Battery Condition: A healthy battery is essential for proper operation of the telematics system.

• Used OEM: $50 - $200
• New Aftermarket: $100 - $300
• Labor Cost: $50 - $200 (if professional installation is required)
• Total Job Cost Estimate: $100 - $500

• Some vehicles may experience issues with the telematics system after a software update.
• Check for any Technical Service Bulletins (TSBs) related to the telematics system on your specific vehicle.
• Some owners have reported issues with OnStar connectivity after replacing the module.

• Check OnStar Functionality: Test the OnStar system by pressing the blue button or using the OnStar app.
• Verify Remote Key Fob Operation: Test the remote lock, unlock, and start functions.
• Check GPS Navigation: Ensure the GPS navigation system is working properly and accurately.
• Scan for DTCs: Use a scan tool to check for any new diagnostic trouble codes (DTCs).
• Listen for Unusual Noises: There should be no unusual noises coming from the module after installation.

Q: Will this module need to be programmed to my vehicle? A: Yes, most likely. The module will likely need to be programmed to your vehicle's VIN by a qualified technician.

Q: What happens if I don't program the module? A: The module may not function properly, and you may experience issues with OnStar, remote key fob, and GPS.

Q: Is it difficult to install this module myself? A: The physical installation is relatively straightforward, but programming requires specialized equipment.

Q: How do I know if this module is the problem? A: Common symptoms include loss of OnStar connectivity, remote key fob issues, and GPS malfunctions. Have a mechanic diagnose the issue to be sure.

Q: What kind of warranty comes with a used OEM module? A: Warranty coverage varies depending on the seller. Check the seller's warranty policy before purchasing.

OEM Part Numbers:

• GM: 84721683, 84822377, 84873689, 84979014, 85128150, 85129368, 855388

Fits Years: 2020 2021 2022 2023 2024