Nissan Blind Spot Warning Not Working: An In-Depth Troubleshooting Guide

Nissan’s blind spot warning system, also known as Blind Spot Intervention (BSI) or Blind Spot Warning (BSW), utilizes sensors and warning lights on the side mirrors to detect vehicles in hard-to-see adjacent lanes. 

It warns the driver both visually and with an audible alert so you can avoid hazardous lane changes. 

But this safety feature naturally causes concerns if it suddenly stops working as it should be. 

Troubleshooting Steps That You Can Take

Review the comprehensive troubleshooting advice below on a non-functioning blind spot system before paying for an expensive dealership diagnosis:

Check the Blind Spot Warning Fuse

• Before assuming complex sensor failures, check that the power is actually reaching your vehicle’s BSI control module. 

• The BSW fuse in the fuse box provides dedicated protection. 

• Review the fuse diagrams in your owner’s manual to locate the correct one. 

• A continuity test or visual inspection will confirm if that fuse has blown. 

• If so, swap in a new fuse of the same amp rating as listed on the diagram. 

• If that replacement immediately blows too, an underlying short circuit exists in the BSW electrical system or sensors. 

• Have the entire circuit diagnosed by a professional before the drain damages other vehicle electronics. 

• If the fresh fuse succeeds in restoring blind spot alerts, move on to software resets.

Perform System Software Reboots

• Like most advanced assist features, Nissan ties the operation of the blind spot monitoring system to vehicle power cycles and ignition sequences managed by onboard computers.

• Attempt to reboot those computers in case of finicky software glitches before investigating hardware issues with the BSW system itself. 

• Key resets are typically sequences like: quickly turning ignition fully on-off-on-off-on. Or holding down both steering wheel control buttons for 10+ seconds until the infotainment screens reset. 

• If properly completed, the Nissan safety system should reactivate upon your next engine start by confirming a temporary software hiccup rather than actual sensor damage.

Verify the Latest Software Installation

• Alongside with the onboard computer reboots, check whether the Nissan has released any updated software patches relevant to your vehicle’s blind spot warning functionality. 

• Much like smartphones, automakers continually optimize performance and fix bugs via “over-the-air” updates to a car’s central processors. 

• Dealers can easily check for pending infotainment or sensor updates that could restore proper operation rather than needing immediate hardware repairs. 

• While not usually free, software flashes are vastly cheaper than replacing an entire Blind Spot Warning assembly and radar sensors just for remedial bugs.

Scan for Diagnostic Trouble Codes

• Most late-model Nissans have built-in self-diagnostic capabilities that are able to detect issues within the Blind Spot Warning system. 

• When automatic self-tests identify a problem, vehicles log unique Diagnostic Trouble Codes (DTCs) which professional scan tools or dealer computers can later access for insights on exactly which components may have failed. 

• Before paying for random parts replacements, considering this solution may solves your BSW problems. 

• Visiting a repair shop to scan all modules for relevant DTCs may points to the root cause. 

• The code’s definition will reveal if trouble stems from a glitched controller, faulty wiring, bad sensors, antenna malfunction, or other specific fault to address.

Inspect the Blind Spot Warning Sensors

• A common cause of the blind spot detection breakdown is obviously a physical damage to the radar sensors attached at the rear corners beneath bumper covers. 

• Impacts from debris, minor collisions, severe weather, or general age can disrupt the outward-staring sensor units. 

• Carefully remove the bumper cover to access and inspect the condition of all blind spot warning hardware. 

• Look for cracks in the housing, broken connectors, penetrating moisture, or detached/misaligned mounting. 

• Even dirt, salt, ice buildup, or sun fading on actual radar lenses can degrade the function. 

• Note any signs of damage for replacement parts or further diagnosis of wiring integrity that leads back to computers.

FAQs About Nissan Blind Spot Warning Not Working

Q: How much does it cost to repair a non-working BSW system?

A: Cost varies dramatically depending on if only software, fuse, or isolated module repairs are needed – or if entire radar sensor assemblies require replacement, it may costs $250+ each. 

Q: Can aftermarket accessories interfere with Blind Spot Warning operation?

A: Yes! Certain add-ons like trailer hitches, light bars, or ham radio antennas can block the radar sensor zones by confusing detection system performance.