Are you wondering what the "service engine soon" light means for your car?
You've come to the right place!
In this PopularMechanic article you will learn:
- What Does The Service Engine Soon Light Mean?
- What Can Cause The Service Engine Soon Light?
- Is The Service Engine Soon Light The Same As The Check Engine Light?
And much more!
The appearance of an unfamiliar light on your vehicle’s dash is never a welcome sight. For many, seeing such a light causes panic, and brings to mind thoughts of being stranded on the side of the road.
While the illumination of certain warning lights can indeed be cause for concern, this is not necessarily the case with a “service engine soon” light.
This particular light varies in different meanings from one manufacturer to the next and has changed by definition with the passing of years.
In fact, a service engine soon light can be telling you that your vehicle is due for service, or can be alerting you of a malfunctioning mechanical or electrical component.
If this seems somewhat confusing, that is understandable. However, the following guide will provide clarity, and answer all of the questions that we know you have regarding your car’s service engine soon light.
Before we begin, there are a few things to keep in mind. Doing so will assist you in quickly and efficiently determining the root cause of your vehicle’s newly illuminated dash light.
- Not all service engine soon lights indicate a “problem”
- Your vehicle’s owner's manual is your best friend when determining what a service engine soon light means
- When in doubt, consult the service department at a brand-specific dealership that specializes in your make of vehicle.
What Does The Service Engine Soon Light Mean?
The meaning of a service engine soon light is highly variable, and dependent upon a vehicle’s year, make, and model. Some vehicles, especially those before the inception of OBD2 technology in 1996, used a service engine soon light in the same manner as a check engine light.
In these cases, an emissions-related issue had been detected by the vehicle’s on-board computer. The service engine soon light would then illuminate to alert car owners of potential problems.
Some General Motors Products, as well as many Nissan vehicles continued to use a service engine soon light for several years beyond the mandated OBD II conversion.
Alternatively, many vehicles began using a service engine soon light to signal that the preset mileage standard for basic service had come due.
This is the case in most vehicles produced in the last ten years.
This is simply meant to alert drivers that their car, truck, or SUV requires an engine oil change, or other scheduled maintenance.
The difference between these two different uses of a service engine soon light can be quickly determined by consulting your vehicle’s owner’s manual.
Read More >> How Do You Install A Remote Car Starter Yourself?
What Can Cause The Service Engine Soon Light?
The root cause of a service engine soon light is dependent upon what the message itself signifies for a particular vehicle.
For many of today’s vehicles, the root cause of a service engine soon light is nothing more than a maintenance interval that has been reached and recorded by the vehicle’s computer.
On the other hand, if a particular vehicle is using a service engine soon light in place of a check engine light, the causes of such an issue can be more complex.
Service engine soon lights that operate as a vehicle’s malfunction indicator, illuminate to notate an out of specification condition that has been cataloged by an ECM (Engine Control Module).
Fault codes set during these out of specification events are generally stored when the car's computer senses that less than optimal operating conditions have increased emissions output beyond expected levels.
Common causes of such issues can include a failed or stuck EGR valve, misfires like those cause by fouled spark plugs or a failing ignition coil, faulty oxygen sensors, a clogged catalytic converter, a loose gas cap, and out of range temperature or pressure readings, among numerous others.
In any event, further diagnostics will need to be conducted on the affected system.
Is The Service Engine Soon Light The Same As The Check Engine Light?
In many older vehicles, the service engine soon, and check engine light were used interchangeably, with both indicating an operational fault of varying severity.
However, most vehicles today have now reserved the use of a service engine soon light for indicating when an engine oil change or other form of basic maintenance is needed.
The best method for determining what your vehicle’s service engine soon light means is by referencing its owner’s manual.
Inside, you will find complete descriptions of what each dash light signifies when illuminated. For more on what these lights mean, check out this article.
Read More >> How Do You Clean A Spark Plug?
What to do when the Service Engine Soon light Appears?
The first thing to do when your vehicle’s service engine soon light appears is to take stock of your car’s dash gauges.
If any of these gauges seem to fall outside of their normal operating range, pull over and shut off your vehicle as soon as it is safe to do so.
This minimizes the chance of engine damage, in the event that a true mechanical fault exists.
If all gauges seem to display normal readings, continue to your destination if it is nearby. Once you have arrived, consult your owner’s manual for further details related to the origin of the light.
If your vehicle’s service engine soon light simply designates the need for regular maintenance, make an appointment to have such service items addressed, or make plans to do so yourself.
In the event that your vehicle’s service engine soon light indicates a mechanical or electrical fault, further diagnoses will be required.
The particular fault code that caused this light to illuminate can be identified through the use of a scan tool.
This fault code can be read by nearly any professional shop. Alternatively, many auto parts stores will pull fault codes from your vehicle as a complimentary service. In any event, the root cause of this fault code should be identified and remedied as soon as possible.
Read More >> What Does A Bad Spark Plug Look Like?
Can You Drive With The Service Engine Light On?
The appearance of a service engine soon light does not necessarily mean that your vehicle is out of commission.
If your vehicle’s service engine soon light designates the need for regular maintenance, it is perfectly fine to continue driving until such tasks can be addressed.
However, do not prolong maintenance items for prolonged periods, as wear and tear to your engine and other functional components can be accelerated.
If your vehicle’s service engine soon light displays when an engine fault has been detected, drivability can be affected. However, in most cases, a vehicle will still be drivable, although with less than optimal performance.
In this case, further diagnosis and repair should be conducted at the first available opportunity to minimize the chance of secondary damage to vehicle components.
Read More >> What Are The Best Car Battery Chargers?
Final Thoughts On Solving the Service Engine Soon Light
Although the appearance of unfamiliar dash lights can be quite concerning, this scenario is often not as troublesome as one might think.
In the case of a service engine soon light, your car might just be giving you a friendly reminder that it is due for maintenance. In other cases, a minor out of range fault might be the reason for your newly illuminated dash light.
In any event, it is always best to consult your vehicle’s owner’s manual for clarification as to a service engine soon light’s meaning.
This minimizes confusion, provides you with a plan of action, and ensures that your car is ready for the many miles ahead.