Q: What Causes Dash Warning Lights to Flash?

There are many dash warning lights on your instrument cluster or dashboard. The one that stands out the most is the one that gets the most attention in most cases. These different warning lights come in different colors like red, yellow, amber, green, blue, or other colors a manufacturer wants. The colors red, yellow, and amber are the ones used most for problems in the vehicle. The other colors like blue or green are used for information to tell you something is being used like cruise control or high beam headlights.

Red or yellow is used for problems with the engine, transmission, electronic steering, anti-lock brakes, suspension, or other major systems that may be having a problem. Many people ignore a light coming on if they do not feel any issues with their car’s performance. Some may even put off getting it serviced until having to pass emissions testing. The light that is on is an alert that something is not working as it should, but today’s vehicle systems try to keep the vehicle running as if nothing is having a problem and only turn on the light since a sensor is bad. The car can use a redundant sensor or alternate input to keep the engine running well enough to not exceed exhaust emissions levels. https://www.yourmechanic.com/services/brake-light-is-not-working-inspection

If there is major concern that the problem will cause harmful damage to one of the engine or powertrain components, emission levels to exceed limits, or a safety concern, then the manufacturer will cause the warning light to flash on and off. The yellow Check Engine Light may flash when the engine has a misfire, causing an excessively rich engine that could cause catalyst damage and excessive emission levels. The Low Fuel Light may blink to let you know you are about to run out of fuel. The Airbag Light may flash to let you know there is a problem with the airbag that would keep it from deploying in case of an accident. You may get an Anti-Lock Brake Light that flashes during a self test, then stays on alerting of a problem in the brakes. The list goes on and on. The manufacturer can have any light they deem important to flash when there is a problem. https://www.yourmechanic.com/services/temperature-warning-light-is-on-inspection

The bottom line here is that a light coming on and staying on is a problem that needs to be fixed. The manufacturer makes the light flash so you will take extra notice and get to a safe stop as soon as possible and get the problem looked at now. If you have a light flashing in your car, do not wait to get it looked at and diagnosed.