C1172 on 2024-2025 Chevrolet Traverse: TPMS Relearn Failure Causes and Fixes

What's Unique About the 2024-2025 Chevrolet TRAVERSE

The 2024-2025 Traverse uses GM's modern Global B electrical architecture, which relies on high-speed Ethernet for communication between key modules, a significant change from older CAN bus systems. Unlike older vehicles where a TPMS issue is almost always a dead sensor battery, this specific failure is due to a design flaw. A Technical Service Bulletin (TSB #24-NA-166) identifies electromagnetic interference from the OnStar module (also called the Telematics Communication Platform or TCP) as the root cause. The interference stems from an improper ground at the module's X7 connector, which disrupts the low-frequency signal required for the TPMS relearn process.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• TPMS warning light is illuminated on the dashboard
• "Service Tire Monitor System" message on the driver information center
• Inability to complete the TPMS relearn procedure, especially for the front tires.
• Tire pressure readings are missing for one or more tires in the vehicle information menu
• The issue may appear randomly or intermittently.

Most Likely Causes

1. Ethernet Communication Interference from OnStar Module 🔴 High Probability This is a documented design issue on the 2024+ Traverse and its platform mates (Acadia, Enclave) related to the new Global B electrical architecture. The OnStar (TCP) module's Ethernet cable has a grounding issue at its X7 connector, causing interference that disrupts the TPMS relearn signal.
   How to confirm: A GM dealership technician will verify the code and the inability to learn the front TPMS sensors. A key diagnostic step outlined in TSB #24-NA-166 is to gain access to the OnStar module, disconnect the X7 connector, and attempt the relearn procedure again. If the sensors can be learned with the connector unplugged, the TSB repair is confirmed as the correct fix.
   Typical fix: Install a specific Ethernet cable overlay harness (GM Part Number 26501515) as per the instructions in TSB #24-NA-166. This involves routing a new cable and transferring the connector housings from the old cable to the new one. This repair is performed under the vehicle's Bumper-to-Bumper warranty.
   Est. part cost: $30-$50

Rare But Worth Checking

• Faulty TPMS Sensor: → Shop Tire Pressure Monitoring System (TPMS) Sensor While a single sensor can still fail due to a dead battery or physical damage, both TSB #24-NA-166 and the preceding document PIT6188B explicitly advise against replacing TPMS sensors before investigating the communication issue first. If the issue only affects a rear tire, it is likely not related to this TSB.
• Body Control Module (BCM) or Radio Frequency (RF) Hub Issue: In very rare cases, the module responsible for receiving the TPMS signals could have an internal fault, but all other more common causes should be ruled out first.

Diagnosis Steps

1. Verify the presence of code C1172 (or C1171, C1173, C1174) with a professional OBD-II scanner.
2. Attempt to perform the TPMS relearn procedure using the vehicle's infotainment screen or a TPMS tool.
3. If the relearn fails, specifically for one or both front tires, consult GM Technical Service Bulletin #24-NA-166.
4. Confirm the vehicle falls within the scope of the TSB (2024-2025 Traverse, Acadia; 2025 Enclave).
5. As a definitive test, gain access to the K73 Telematics Control Module (OnStar Module) by lowering the rear of the headliner.
6. Disconnect the X7 Ethernet connector from the module and attempt the TPMS relearn again. If the sensors now learn successfully, the TSB applies.
7. Proceed with the repair outlined in the TSB, which involves installing the overlay harness (P/N 26501515).
8. If the TSB does not apply or the issue persists after the repair, begin standard diagnostics for the individual TPMS sensor and its circuit.

Parts You'll Likely Need

• Ethernet Cable Overlay Harness (OEM #26501515) — This is the specific part required to fix the communication interference from the OnStar module, as documented in TSB #24-NA-166. It is described as 'CABLE,BODY WRG HARN MODULAR PAIR'.
  Trusted brands: Genuine GM
  OEM price range: $30-$50
  Aftermarket price range: N/A

Related Codes That Often Appear With This One

• C1171 — This code is for a different wheel position but is caused by the exact same OnStar module interference issue described in TSB #24-NA-166.
• C1173 — This code is for a different wheel position but is caused by the exact same OnStar module interference issue described in TSB #24-NA-166.
• C1174 — This code is for a different wheel position but is caused by the exact same OnStar module interference issue described in TSB #24-NA-166.

Technical Service Bulletins (TSBs) & Recalls

• Bulletin #24-NA-166: This is the primary service bulletin that supersedes earlier preliminary documents. It identifies interference from the OnStar module due to a grounding issue at the X7 connector as the cause for DTCs C1171, C1172, C1173, and C1174. It provides the full service procedure to install the Ethernet cable overlay (P/N 26501515). It explicitly notes the issue affects the front tires and the repair involves extensive interior trim removal.
• Bulletin #PIT6188B (Superseded): A Preliminary Information bulletin that preceded the final TSB. It first identified the OnStar module interference as the cause and instructed dealers *not* to replace TPMS sensors. It also detailed the diagnostic step of accessing the module in the headliner.

Platform-Specific Known Issues

• A known issue documented in TSB #24-NA-166 describes how electromagnetic interference from the OnStar (Telematics) module can prevent the TPMS sensors from completing a relearn procedure, setting codes C1171, C1172, C1173, or C1174. The cause is a grounding issue with the module's Ethernet cable. The fix is a dealer-installed wiring overlay harness and is typically covered under the factory warranty.

Scan Tool Commands That Help

• GDS2 / Professional Scan Tool: TPMS Learn Mode — A technician uses this command to force the vehicle into the relearn state. On the 2024-2025 Traverse, if this command is initiated but the front sensors fail to learn, it strongly indicates the interference issue from TSB 24-NA-166 is present.
• Vehicle Infotainment System: Sensor Relearn — This is the owner-facing method to start the relearn process, typically found under Vehicle Settings > Tire Pressure. Failure to learn the sensors using this method is the primary symptom that leads to diagnosis.

Wiring & Ground Locations

• K73 Telematics Communication Platform (OnStar Module) — Located above the headliner in the rear 🎬 Watch: A guide on accessing and removing the OnStar module. of the vehicle. Access is gained by partially lowering the rear of the headliner near the liftgate opening.. This module is the source of the electromagnetic interference that disrupts the TPMS relearn procedure.
• X7 Connector — A connector plugged directly into the K73 Telematics module.. TSB #24-NA-166 identifies an improper ground at this specific connector as the root cause of the interference. Disconnecting it is the key diagnostic step to confirm the fault.
• X205 Connector — An Ethernet cable connector located in the right-hand front passenger compartment.. The TSB repair procedure involves disconnecting the original Ethernet cable at this location and connecting the new overlay harness here, which then routes to the K73 module.

Real Owner Repair Stories

• Go-Parts.com research on platform-mate GMC Acadia (2024-2025 GMC Acadia (platform mate)) — TPMS warning light on, inability to complete the relearn procedure, codes C1171, C1172, C1173, or C1174 present.
  ❌ Tried (didn't work) Replacing the TPMS sensors.
  ✅ What actually fixed it The issue was resolved by a GM dealer performing the repair outlined in TSB #24-NA-166, which involves installing the Ethernet cable overlay harness (P/N 26501515) to shield the system from OnStar module interference. The repair was covered under the factory warranty.

OEM Part Supersession History

• 26501515 → N/A — This is the current and only specified part for the TSB #24-NA-166 repair.