A ‘Lane keep assist system unavailable’ notification from the system when activated is a warning that the system has been disabled. This is often due to a blown fuse, software glitch, or issues with the system’s line-detecting camera. Installing a wrong tire size, a faulty charging system, and engaging the system for unintended use can also deactivate the lane keep assist.
The lane-keeping assist system is a safety feature that helps drivers stay in their lane. Depending on the automaker, the system uses a front-facing camera and some sensors. These components work together to detect lane markings. And notify drivers when deviating out of their lane without a turn signal activated.
The lane keeps assist system needs all its components to operate. Else, the system will become inoperable. Once the system stalls, it displays ‘Lane Keep Assist System Unavailable’ or ‘Lane Centering Assist Not Available’ on the DIC when the system is activated.
All your vehicle electrical systems, including the lane keep assist, are tied to a fuse. The fuse ensures that these systems don’t short-circuit or get swamped with excess current.
The corresponding fuse for the lane keep assist is the first place to look whenever the system stalls. Another sign that you have a bad fuse is if the front collision warning system also stalls alongside the lane assist. And both systems failed without any evident damage to their sensors or camera.
Or if you drive a recent-generation GM truck or SUV, and the lane keep assist fails, a bad fuse is the likely culprit. The company even issued a TSB acknowledging the issue. And suggested that removing the fuse for about ten seconds would solve the problem.
Replacing the blown fuse is relatively easy. Refer to your owner’s manual or do a quick google search to locate the corresponding fuse for your lane assist. For owners of GM vehicles, remove the old fuse for some seconds and reinstall it to see if the system works. Removing the fuse does a hard reset for the lane keep assist system.
But if that doesn’t work, you’ll have to replace the fuse. The fuse is a 10 amp fuse in the passenger side dash fuse box.
Issues with the camera
The system relies on a camera mounted behind the windshield to detect the line marking on the road. A dirty camera or windshield tint can impair camera visibility. Inclement weather conditions like snow, rain, and fog also reduce the camera performance.
Obstruction of the camera’s visibility impacts its ability to detect lane markings. The system will temporarily disengage until the obstruction is gone.
Cleaning the camera or removing the windshield tint should reactivate the system. But if you are dealing with inclement weather, you’ll have to wait until the weather is back to normal. And if the camera is broken, you’ll need to get it replaced.
Installing incorrectly sized tires
Driving with the wrong tire size can trigger a ‘lane keep assist system unavailable’ warning. The tire disparity creates a wheel speed discrepancy when the vehicle is cruising.
Since the lane keep assist relies on the wheel speed data, the system disengages anytime there is a discrepancy in the report. The other driver-assist features that also rely on the wheel speed data will also stop working.
If you recently replaced one of your tires, you should check that it is OEM and the same size as the others. Installing anything outside the manufacturer’s recommendation will create a wheel speed discrepancy.
A software issue can also disable the system and prompt a ‘lane keep assist system unavailable’ warning. Reports of software glitches are rampant among GM owners. The drivers complained of losing the lane keep assist after having recalls done.
A software update or system reset is a possible solution. For the GM vehicles that lost their lane keep assist feature after software recalls, putting the front camera into learn mode will help recalibrate the system.
During the relearn process, you’ll have to drive on a well-marked road while driving at a speed above 36mph.
Faulty charging system
A failed charging system can also disable the lane keep assist. The vehicle charging system provides the electrical charge that powers the electrical systems. Whenever the charging system fails, the battery powers the electrical systems.
The battery can only power the electrical system for so long before it also runs out of charge. And since the lane assist needs power to run, the system will stall once there is an issue with the power supply.
Besides the failed lane keep assist, dim headlights are also indicators that you are dealing with a faulty charging system. To resolve the power issue, you must find out the source of the problem. Start with the battery and check that it is holding enough charge. And check the alternator to be sure it is putting out the right amount of charge.
Engaging the system in unintended situations
The lane keep assist system won’t work if you attempt to use it in situations it wasn’t intended for. These systems were designed for use on highways when driving at speeds above 36 mph, and both lane markings are visible.
The system won’t engage if you are trying to activate it while driving under these speed levels. Also, if the line markings on the road aren’t visible, the system may have difficulty detecting them. Most systems, especially GM vehicles, will not function in parking lots or on gravel roads.
The breakdown of one of the lane keep assist system components will cause it to malfunction. It notifies the driver by displaying a ‘lane keep assist system unavailable’ message every time the driver activates the system.
The failure could have resulted from several causes. From a blown fuse to low camera visibility, software glitch, faulty charging system, or installing the wrong tire size.
A blown fuse and low camera visibility are often the cause of the failure. And losing the front collision warning feature at the same time the lane keep assist system stalls is an indicator that you have a faulty fuse.