BLIS System Fault on 2016 Ford Edge Titanium

ClearTheCode admin answer:

1. Check for Physical Damage & Obstructions: The BLIS sensors are typically located behind the rear bumper cover, often near the corners. Visually inspect the bumper cover in these areas for any signs of impact damage, cracks, or debris that might be blocking the sensors. Ensure the bumper is clean and free of dirt, ice, or heavy snow, which can interfere with sensor operation.
2. Scan for Diagnostic Trouble Codes (DTCs): A BLIS fault will almost certainly store specific B-codes (Body) or U-codes (Network Communication) in the vehicle's modules. Common codes include B1B68 (Left BLIS Sensor), B1B69 (Right BLIS Sensor), U0159 (Lost Communication with Blind Spot Monitoring Module Left), U0160 (Lost Communication with Blind Spot Monitoring Module Right). These codes help pinpoint if it's a sensor, wiring, or module communication issue.
3. Wiring Inspection: Intermittent faults can sometimes be due to damaged or corroded wiring harnesses leading to the BLIS sensors or module. This is harder to check without removing the bumper cover.
4. Causes: The most common causes are a faulty BLIS sensor (often due to water ingress or internal failure), damaged wiring, a communication error with the Body Control Module (BCM), or rarely, a faulty BLIS control module itself.
5. When to See a Shop: If a visual inspection doesn't reveal any obvious damage, and especially if you're getting specific DTCs, it's best to take your Edge to a qualified technician. Diagnosing BLIS issues often requires specialized diagnostic tools to communicate with the BLIS modules, test sensor functionality, and check wiring continuity, which can be complex due to their location and integration with other vehicle systems.