Our certified mobile mechanics come to you 7 days a week between 7 AM and 9 PM.
How A Diagnostic Works
Instantly book a certified mobile mechanic to come to you
Mechanic diagnoses the problem and quotes necessary repairs
Your vehicle is ready to go
Fair, upfront & transparent pricing for all services
Our certified mobile mechanics can come to you now.
On average, the cost for a Mercedes-Benz S400 Check Engine Light is on Inspection is $95 with $0 for parts and $95 for labor. Prices may vary depending on your location.
The Check Engine Light can be one of the most confusing warnings in your dashboard cluster because it offers no explanation as to why you suddenly need to check your engine. It sounds ominous and can be as serious as a malfunctioning catalytic converter or as trivial as a loose gas cap.
The Check Engine Light location and color will vary by vehicle, but in most cases it is a dashboard warning light that is yellow and shaped like an engine. It may or may not have the word “check” integrated into the design.
This indicator is part of the onboard diagnostics (OBD-II) system and in all cases it indicates a problem with your emissions system. Basically, it is an emissions monitoring system. A Check Engine indicator will stay solid or blink.
If the indicator is blinking, the situation is usually serious, such as a severe misfiring of the engine. This would allow unburned fuel to dump into the exhaust system, pushing the temperature of your catalytic converter to the breaking point. Slow the car down, find a safe place to stop, and request a mechanic to perform a diagnosis.
A steady light on the other hand is not an emergency situation. You can continue driving, but you should schedule an appointment with a mechanic as soon as possible.
While a Check Engine Light can come on for a number of reasons, in most cases it is due to one of the following issues:
When that annoying yellow light pops on, the first thing you should do is pull over and inspect your gas cap. If it is loose, a quick tighten could very well solve your problem. If it is damaged, head to your local auto parts store for a new one.
Once you have fixed the issue, continue driving to see if the check engine light turns off. If the light stays on, schedule an appointment with a mechanic.
Deterioration of the precious metals inside the oxygen sensor affects the sensors’ ability to give an accurate reading. If you put off getting an oxygen sensor replaced, it will eventually damage your catalytic converter, which can be very costly to replace. Your best bet is to call a mechanic and get a proper diagnosis.
In most cases, a catalytic converter will not fail if you properly maintain your car. A failing converter can be the result of a faulty oxygen sensor that has not been replaced or any other engine efficacy issue.
A broken catalytic converter will eventually bring your car to a complete stop. Before that, your gas mileage will be horrid, the car will not run smoothly, and the car will not pass an emissions test. A damaged converter should be replaced immediately.
An air filter that has never been replaced or improperly installed can sometimes be the culprit when it comes to a faulty mass airflow sensor. Have your air filter checked and replaced on a yearly basis.
While it is possible to drive for months with a malfunctioning mass airflow sensor, it’s not a good idea. Your gas mileage will drop and the car will start stalling frequently. It is best to call a mechanic and have the sensor diagnosed and replaced if necessary.
While newer cars can go 100,000 miles on a set of plugs, older vehicles, especially those built before 1996, require new plugs roughly every 30,000 miles. There is no way to prevent plugs from failing, it just happens over time. If spark plugs are your issue, get them replaced immediately. A mechanic can make quick work of the job and new plugs in most cases are very affordable.
A top-rated mobile mechanic will come to your home or office to identify the source and cause of the illuminated Check Engine Light, and then check other system components as specific symptoms and issues are identified.
After the inspection, the mechanic will provide a detailed report that describes the diagnosis, along with the scope and cost of the necessary repairs.
When the Check Engine Light is on, your car’s monitoring system will have "fault codes" that indicate the nature of the problem. Your car may have one or more problems and hence there can be multiple codes.
The mechanic will read the codes using a scanner, interpret the codes, and provide a diagnosis. If you approve the repair estimate, they will replace the faulty part(s), clear the memory of any fault codes, turn the Check Engine Light off, and let you drive the car for a few days to see if the light comes back on or not.
Please note: It may take several days of driving the car for the monitoring system to verify that the repair has fixed all the problems. If the monitoring system fails any of its internal tests, it will turn the light back on. This means that the car has more problems that were not evident during the first evaluation. The mechanic will have to perform further diagnosis and create new repair estimates for resolving the problems found. In some rare cases, multiple visits may be required to diagnose and resolve the stubborn Check Engine Light issues.
A blinking Check Engine Light indicates a critical issue, whereas a solid light reflects a non-emergency situation. Once you rule out a loose gas cap, it’s imperative a mechanic diagnoses the issue as soon as possible.
Fast and easy service at your home or office
Backed by 12-month, 12.000-mile guarantee
Real customer reviews from Mercedes-Benz owners like you.