“FCW System Malfunction” means that the system is not able to warn you of an imminent crash. If it fails, you won’t be notified of the hazardous situation.
The FCW is separate from any Advanced Driver-Assistance Systems (ADAS) that might control brakes or steering. It’s simply a warning.
So, is it vital when the FCW system fails?
Not directly. It’s generally easy to fix, but it might also mean that you have a more severe underlying ECU problem.
I’m prepared to help you. Please provide the text you’d like me to edit.
Table of ContentsShow
What Is An FCW System?
The Frontal Collision Warning (FCW) system warns drivers of dangerous situations ahead. It’ll alert you when your speed is disproportionately swift compared to a slower or stationary object in front of you.
Each manufacturer designs its system differently. However, in general, most use a combination of at least two of the following:
- Cameras
- Radar sensors
- Lasers
The FCW system can be immensely beneficial if you’re a distracted driver.
Depending on the system and description, the exact caution differs. Most vehicles will issue an audible notification (commonly a beep) and/or vibrate the physical steering wheel.
When the FCW system alerts you of looming danger, you must look up, assess the situation, and respond appropriately.
The FCW system is a driver assist, not an all-knowing deity. It can get things wrong. Don’t slam the brakes on for no reason – this could lead to a collision behind you.
The FCW system won’t function in various circumstances, including:
- Seeing oncoming traffic.
- Being aware of traffic heading perpendicularly across your path.
- Registering “small” road users (pedestrians, motorcyclists, cyclists, horses, etc.).
- Always take particular care when behind any road user, especially the most vulnerable.
FCW System Failure: What Should I Do?
If you read the “FCW System Failed” message on your car’s display, keep a watchful eye on the road ahead.
Your car shouldn’t automatically apply the brakes, even if it has ADAS programs. The system turns itself off to avoid creating hazardous accidents.
Keep driving until you come to a safe place to stop, such as a rest stop, parking lot, or lay-by. Then,
- First, restart your car. The error message might not come back. The vehicle is safe to drive.
- If the error message returns, clean the front of your car down. If possible, do a complete and thorough car wash. This might remove any substances blocking a sensor or camera.
- Failing this, ensure the FCW system is off. You’ll find instructions on doing this in your owner’s manual. Now, continue to drive, heading to see an automotive electrician at your earliest convenience.
The FCW system is only a “warning.” It doesn’t control the brakes for you (although it might be linked to such a program).
An FCW system failure only means you won’t be alerted of a collision. Your car is safe to drive as normal. Keep an extra vigilant lookout for anything stopped ahead of you (but you should always be doing that, anyway).
Which Part Of An FCW System Fails?
The error message “FCW System Failed” means that the Frontal Collision Warning system isn’t functioning. That much is obvious.
But which section?
The FCW system could fail with:
- Driving beyond the system’s limits
- Road conditions
- Traffic conditions
- Environmental conditions
- Sensor (or camera or laser) failure
- Electrical problems
- Physical damage
- Poor-quality part
- Electrical wiring
- ECU/command module failure
ECU or sensor failure is too complex to work on at home. Take your car to a specialized electrical mechanic or a dealership.
Driving Beyond The System’s Limits
Fortunately, this is the most common reason for the “FCW System Failed” warning.
When you’re driving in particular conditions (whether it’s the road, other cars, or weather/environmental factors), the FCW can’t work. The sensors and cameras can’t scan the road ahead.
Here are a few examples of this.
- In heavy rain or snow, there’s no clear view of the space in front of the car.
- The same applies when in thick fog, mist, or dust storms.
- Other radar sources interfering with a sensor.
- Driving through a tunnel.
- Ice or snow might sit on and cover sensors or cameras.
- When driving on narrow, winding roads.
- Traveling up and down hills (especially cresting and reaching the bottom).
- Driving too close to the car in front.
- The manufacturer may have installed a specific speed range at which the FCW system works.
Additional factors may also be involved. It is recommended to regularly stop at the closest safe location and switch off your car. Remove any debris from your vehicle (if necessary) and restart it.
The “FCW System Failed” message will often not reappear. You’ve done it. Give yourself a hearty pat on the back, and get on with your day.
If the error message persists, there’s a more profound issue.
FCW Sensor Failure
If the FCW system fails, there could be an issue with a defective sensor, laser, or camera.
As mentioned, there isn’t a typical arrangement that all manufacturers use – not yet, at least. You’ll need to consult your owner’s manual to find the different locations.
However, this is the Frontal Collision Warning system. All the sensors, consequently, will be somewhere close to the front.
- There’s usually a camera behind the windshield.
- Radar and laser sensors can be located in the grille or front of the fenders.
It should be as straightforward as replacing the defective sensor with a new one.
This failure could stem from several places. For instance, the original part might be substandard or from an affected batch from the manufacturer’s supplier. The sensor could have been physically damaged in a crash or by water intrusion. It might have simply suffered from general wear and tear.
Either way, you require a new one.
After all this, it may just involve modifying a sensor. When you get a new windshield or sensor piece, it is a wise idea to have this done.
Electrical Wiring & Connections
If all the sensors are in proper order, the fault might lie with the wiring.
All sorts of things could go wrong here. Here are a few examples:
- Wire sleeves could break and lead to corrosion.
- Rodents are attracted to the environmentally-friendly soy materials used in modern cars.
- There could be a loose connection.
- A grounding cable might be loose or shorting.
- A fuse could have blown or come loose.
You’ll need a thorough electrical diagnosis from a professional if you find sensors aren’t the problem.
ECU/Command Module Failure
A problem in the ECU is the most difficult to diagnose. But if wiring or sensors aren’t the issues, it’s the sole alternative left.
Control modules can get damaged in numerous ways. One of the most common is water or moisture ingression and physical accidents. There could also be a manufacturer glitch or incorrectly installed hardware, among many other things.
You could try doing a reset. This often involves removing a fuse or disconnecting a battery for a specific period (around 15 to 30 minutes). The control modules then revert to their default settings. Check your owner’s manual before doing this to avoid additional damage!
In some instances, this fixes glitches and fleeting, less significant issues.
Failing that, you’ll need some modification work.
Don’t even think about replacing or reprogramming your ECU yourself. The intricate aspects involved are fiddly, and it’s almost impossible to do at home.
How To Fix A Failed FCW System
In summary of this, then, the ideal order to try fixing the FCW system is:
- Cleaning the front of your car.
- Restarting your engine.
- Control reset (check your owner’s manual!).
- Go directly to an automotive electrician.
- You could go to a local mechanic. However, they’ll likely subcontract the work to a specialist and charge you a marked-up rate. It’s cheaper to go straight to the (already expensive) source.
In the end, an FCW system malfunction isn’t the end of the world. You can drive without it, no problem. But it’s ideal to get it fixed because it might indicate there’s a more substantial internal fault.
If your car is still covered by its warranty, excellent! This should all be covered for free.
Catch it early? Catch it cheap.
