U0075 on 2018 Chevrolet Traverse: Driver Assist & Communication Fault Causes

What's Unique About the 2018-2018 Chevrolet TRAVERSE

The 2018 Traverse was the first model year of the second generation, which introduced a suite of Advanced Driver-Assistance Systems (ADAS) on the C1XX platform. Code U0075 is directly tied to this new, complex network. GM issued a Technical Service Bulletin (PIT5441C) that covers this exact code and vehicle, pointing technicians to diagnose the Object Detection System. A unique aspect is that the TSB warns that a technician's own faulty diagnostic tool cable (MDI/MDI 2) can sometimes induce this code by interfering with pins 3 and 11 on the diagnostic port, a rare diagnostic trap.

Diagnostic Flowchart

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

Symptoms You May Notice

• "Service Driver Assist System" message on the instrument cluster.
🎬 Watch: How to fix and reset driver assist warning messages.
• Warning lights for systems like Stabilitrak, ABS, or forward collision alert.
• Lane Keep Assist, Side Blind Zone Alert, and Rear Cross Traffic Alert become unavailable.
• Adaptive Cruise Control may be disabled.
• The OnStar light may turn red.
• The backup camera or surround-view camera system may not function.
• "Side Detection System Unavailable" message may appear at startup.

Most Likely Causes

1. Failed Side Blind Spot Detection Module (Radar Sensor) 🔴 High Probability These modules are located in the rear bumper corners, making them extremely vulnerable to water intrusion, road salt, and debris kicked up by the rear wheels. This leads to severe corrosion that causes the module housing to swell and crack, destroying the internal electronics and connector pins.
   How to confirm: Using a professional scan tool, check for specific codes pointing to the left or right side object sensors (e.g., U026A, U026B). A visual inspection after removing the rear bumper cover will often reveal 🎬 See this walkthrough on how to remove the rear bumper. obvious corrosion on the module or its connector. The modules may be physically swollen or cracked.
   Typical fix: The faulty module must be replaced. After installation, the new module requires programming and calibration using dealer-level software (SPS) to function correctly. In many cases, the connector pigtail must also be replaced due to corrosion.
   Est. part cost: $150-$400
2. Damaged Wiring or Corroded Connectors 🟡 Medium Probability The wiring harness that runs to the rear bumper is exposed to the elements. The main connector for the side detection modules is a common failure point where moisture accumulates, leading to corroded pins that disrupt communication. A user on a GMC Acadia forum confirmed their identical issue was fixed by repairing a corroded connector, even after a shop had already replaced the modules.
   How to confirm: Perform a visual inspection of the harness leading to the rear bumper. Disconnect the connectors for the Active Safety Module and side detection modules and check for green or white corrosion, or bent/broken pins. A multimeter can be used to check for continuity and resistance on the CAN bus wires.
   Typical fix: If corrosion is minor, cleaning the connector pins may work temporarily. For a permanent fix, the damaged connector pigtail should be replaced. Damaged sections of wire must be professionally spliced and sealed with heat-shrink tubing.
   Est. part cost: $20-$80
3. Low Battery Voltage or Poor Ground Connection ⚪ Low Probability Modern vehicles with numerous control modules are highly sensitive to system voltage. An aging battery or a loose/corroded main ground can cause modules to malfunction and drop off the network, triggering communication codes.
   How to confirm: Test the battery's state of charge and health; it should be above 12.4 volts at rest and hold a load. Inspect the main battery ground cable and chassis ground points for tightness and corrosion.
   Typical fix: Replace the weak battery. Clean or tighten loose or corroded ground connections.
   Est. part cost: $150-$300

Rare But Worth Checking

• Faulty Active Safety Control Module: While less common than sensor or wiring failure, the central Active Safety Control Module (located behind the glove box) can fail internally. A Reddit user reported their dealer diagnosed a 'bricked' module that required replacement. This is usually diagnosed after all other possibilities like wiring and peripheral modules have been ruled out.
• Faulty Diagnostic Tool Cable (False Code): As documented in TSB PIT5441C, the specific data bus for the object detection modules can be affected by a faulty diagnostic cable (GM MDI/MDI 2), inducing false U-codes. This is a trap for technicians, where the diagnostic tool itself is the problem, not the vehicle.
• Improper Module Mounting Bracket: TSB PIT5622B notes that if the side detection modules are not perfectly aligned on their mounting brackets inside the bumper (due to damage or improper installation), they can fail self-calibration over time and trigger a 'Side Detection System Unavailable' message, even with no DTCs set.

Diagnosis Steps

1. Scan for all Diagnostic Trouble Codes (DTCs) in all modules. Note which modules are not communicating, paying close attention to the Active Safety Module and Side Object Detection Modules.
2. Check and verify battery voltage and charging system performance. Ensure the battery is fully charged and healthy.
3. Inspect the main battery and chassis ground connections for corrosion and tightness.
4. Consult TSB PIT5441C. If you are a technician, verify your diagnostic interface cable is not the cause of the code by testing on a known-good vehicle or using a loopback adapter.
5. Remove the rear bumper cover for a direct visual inspection of the left and right side object detection modules and their wiring harnesses. Look for physical damage, swelling/cracking of the module case, and green/white corrosion on the connector pins.
6. Using a wiring diagram, check for power, ground, and proper CAN bus resistance (typically 60 ohms when measured at the DLC, or 120 ohms at a module connector if a terminating resistor is disconnected) at the connector of a non-communicating module.
7. If wiring, power, and grounds are confirmed to be good, the fault likely lies with a control module itself (e.g., the side object detection module or the main Active Safety Control Module).
8. Module replacement requires programming and calibration with specialized equipment (GM SPS).

Parts You'll Likely Need

• Side Object Detection Module (OEM #84402182 (Supersedes older numbers)) — This is the most common point of failure due to its exposed location in the rear bumper, leading to corrosion and communication loss. They are often sold as a kit including both modules and a new harness.
  Trusted brands: ACDelco, GM Genuine
  OEM price range: $200-$400
  Aftermarket price range: $150-$300
• Active Safety Control Module (OEM #84737638) — If wiring and peripheral sensors are good, the central control module may have failed internally. Part numbers 84218070 and 84356794 are also related. This module is located behind the glove box.
  Trusted brands: ACDelco, GM Genuine
  OEM price range: $150-$400
  Aftermarket price range: $150-$300
• Wiring Harness Connector Pigtail (OEM #CE8031-3 (Example)) — Used to repair corroded or damaged connectors at the module, which is a common issue that prevents a new module from working.
  Trusted brands: ACDelco, Dorman, Connector Experts
  OEM price range: $40-$80
  Aftermarket price range: $20-$50

Related Codes That Often Appear With This One

• U026A — Indicates lost communication with the left side object detection module, a common cause of the U0075 code.
• U026B — Indicates lost communication with the right side object detection module, another common cause.
• U026C, U0265, U0268, U0269 — These codes are also related to the active safety system and are mentioned alongside U0075 in TSB PIT5441C, indicating a broader network failure.

Technical Service Bulletins (TSBs) & Recalls

• PIT5441C: Provides diagnostic steps for technicians encountering Object Detection System messages and DTCs U0075, U026A, U026B, etc. Critically, it warns that a faulty MDI/MDI 2 diagnostic cable can induce these codes.
• PIT5622B: Addresses a 'Side Detection System Unavailable' message at startup, which can be caused by broken or misaligned mounting brackets for the radar modules, even without DTCs.
• Service Update 18158: While for the 2018 Equinox, it shows a related issue where a software update for the side blind zone alert module was required to fix a 'Service Side Detection' message, indicating software fixes are sometimes the solution.

Platform-Specific Known Issues

• TSB PIT5441C was issued by GM specifically addressing U0075 and related codes on the 2018 Traverse, pointing to issues with the Object Detection System and even the technician's diagnostic tools.
• A Reddit user with a 2018 Traverse confirmed getting the 'Service Side Detection System' message, which eventually stayed on permanently. Another user fixed it by purchasing used sensors on eBay for around $150 and having a me

Mechanic-Grade Diagnostic Values

• CAN Bus Network Resistance — expected: Approximately 60 Ohms measured between Pin 6 (CAN High) and Pin 14 (CAN Low) at the DLC with the battery disconnected.. Failure: A reading of 120 Ohms indicates one of the two terminating modules (or the wiring to it) is offline. A reading near 0 Ohms indicates a short between the high and low lines. A reading of 40-45 Ohms may indicate a third, unintended resistor on the network or a failing module.
• CAN Bus Voltage (Key On, Engine Off) — expected: CAN High (Pin 6 to Ground) should be ~2.6V. CAN Low (Pin 14 to Ground) should be ~2.4V. The two should add up to approximately 5V.. Failure: Voltages that are stuck high, low, or at 0V indicate a short to power or ground on that specific line.
• Side Object Detection Module Connector Pinout — expected: At the 4-pin module connector: Pin 4 should have Battery Voltage, Pin 3 should have continuity to ground, Pin 1 is CAN High, and Pin 2 is CAN Low.. Failure: Absence of voltage or ground prevents the module from powering on. Incorrect resistance or voltage on CAN lines indicates a wiring fault back to the Active Safety Module.

Scan Tool Commands That Help

• GM GDS2 (Global Diagnostic System 2): Side Object Sensor Module Programming and Setup — This function is mandatory after replacing a left or right Side Object Detection Module. It programs the new module with the vehicle's VIN and configuration, then calibrates it to the network. Failure to perform this step will cause the new part to not function and may set additional codes.
• GM SPS (Service Programming System): Active Safety Control Module Programming — Required after replacing the main Active Safety Control Module. This loads the correct software and vehicle-specific calibration into the new module. A stable power supply is critical during this procedure.

Wiring & Ground Locations

• G401 / G402 — Located on the frame rail in the rear of the vehicle, typically behind the rear tire area or near the rear body mounts.. These are the primary chassis ground points for the rear body harness, which includes the Side Object Detection Modules. Corrosion or looseness at these points can cause intermittent power loss and communication faults for the modules, triggering U0075.
• X411 — This is the main inline harness connector that joins the rear bumper harness (containing wiring for the detection modules) to the main body harness. It's typically located inside the rear bumper area or just behind it.. This connector is a major weak point for water intrusion and corrosion. A fault here can cut off communication to both side detection modules simultaneously, making it a prime suspect for a U0075 code that is accompanied by both U026A and U026B.
• Active Safety Control Module — Located behind the glove box compartment.. This is the master module for the object detection bus. All diagnostic paths for U0075 originate here. Technicians need to access its connectors to test the CAN bus wiring before it runs to the rear of the vehicle.

Real Owner Repair Stories

• Acadia Forum (platform-mate) (2018 GMC Acadia Denali) — "Service Side Detection System" message, codes U0075, U026A, U026B.
  ❌ Tried (didn't work) A repair shop replaced both left and right side detection modules, but the codes returned immediately.
  ✅ What actually fixed it The owner traced the wiring harness from the rear bumper forward. About 18 inches from the main X411 connector, under the factory tape, they found a corroded green CAN bus wire that had broken internally. Repairing this single wire by splicing in a new section resolved all codes and restored system function.

OEM Part Supersession History

• 23296223, 84160393, 84186471 → 84402182 — Revisions to improve sealing against water intrusion and updated internal electronics.
• 84218070, 84356794 → 84737638 — Internal hardware and software updates for the Active Safety Control Module.