What does the fuel filter warning light mean?

The engine fuel filter check indicator alerts you when your diesel fuel filter is full and needs to be emptied to avoid engine damage.

Diesel engines are very different from their gasoline counterparts. In addition to not using spark plugs, almost every diesel engine uses fuel to lubricate precision engine components. Unfortunately, trace amounts of water can be found in diesel fuel and must be removed before it enters the engine.

Water does not work very well as a lubricant and can cause excessive engine wear if it gets into the fuel system. To prevent this, diesel fuel filters are designed to separate fuel and water before they enter the engine. Water is collected and must be drained from time to time, otherwise it will begin to seep through the filter and enter the engine.

Some vehicles may drain the water automatically, or you may need to drain it manually. A warning indicator on the dashboard will let you know when too much water has been collected and the fuel filter needs to be emptied.

What does the fuel filter warning light mean?

Inside the fuel filter is a fluid level sensor that monitors the amount of water collected. As soon as the level begins to reach its maximum capacity, the fuel filter warning light comes on to let you know that the filter needs to be emptied.

In manual systems, a valve at the bottom of the filter allows water to drain once opened. If your filter empties automatically and the indicator lights up, it means that an error or malfunction has been detected and needs to be checked as soon as possible. This warning indicator may indicate that the drain is blocked and the system cannot empty itself. A code will be saved on your computer to help you determine the cause of the problem. Check the vehicle with a diagnostic scanner to find the stored code or codes.

Do not ignore this warning signal or the system will fill with water and start leaking into the engine. After the water is drained from the filter, this indicator should turn off by itself.

Is it safe to drive with the fuel filter light on?

Although it is not an emergency when the light comes on for the first time, it is important that you drain the filter as soon as possible. Waiting too long will cause water to accumulate and eventually reach the engine where it can cause serious damage. Remember to change the fuel filter at the correct service intervals, as draining the water will not remove all of the particles trapped in the filter.

Our certified technicians are always available to assist you in diagnosing any problems with your vehicle's fuel filter and they can drain or replace the fuel filter for you.