Seeing the dreaded “Front left malfunction consult workshop” message appear on your Mercedes dashboard can be quite alarming, especially if you don’t know what it means or what could be causing it.
In this article, I am going to explain what this fault message means and the possible causes, let’s get to it.
What Does “Front Left Malfunction Consult Workshop” Mean on a Mercedes?
In simple terms, the “front left malfunction” message on a Mercedes means there is an issue with the left-hand side airbag system.
From my experience working on Mercedes Benz cars, the fault is rarely caused by a faulty airbag itself but rather a problem with wiring or connectors connected to the seat which is related to the SRS airbag module.
Mercedes Front Left Malfunction Possible Causes
Now, Let’s get into the possible causes of this message.
1. Bad Seat Sensor Mat/Pad
As stated above, the most common cause of this message is a bad seat sensor mat.
This is a piece of fabric that fits into the seat and is used to detect when there is a person seating.
It’s connected to the SRS airbag system via wires and a connector which can become frayed or damaged over time due to things like water on your seat and sitting on the mat for too long.
If you’re experiencing a front left malfunction message, it’s a good idea to check your seat sensor mat first on the front left seat.
This pad is located under the seat cushion and is easy to access.
2. Disconnected Wiring Connector Under the Seat
Another possible cause for the front left malfunction light is a disconnected wiring connector.
This is a yellow connector under the left front seat. Check under the front-left seat and look for a yellow plug. If it’s not connected, reconnect it.
3. Blown Fuse
F219 Fuse which is connected to the airbag system is one of the most common causes for the front left malfunction light.
If this fuse is blown, it will prevent airbag deployment on the front left seat and cause a front left malfunction message.
You can test if this fuse is blown by checking it with a multimeter (F219 Fuse is found in your fusebox). If the fuse is blown, you need to replace it with a new one.
4. Faulty Seat Belt Tensioner
A bad seat belt/tensioner on your Mercedes is another reason for the “Front Left Malfunction Consult Workshop” warning.
If your seat belt isn’t connected properly or if it has a loose connection, then you might get this message.
You can check this by checking if both ends of the seat belt are connected to their respective places (behind the seats and on the side of the seats).
5. Bad Airbag Sensors underneath your Mercedes Passenger seat
are the sensors that detect if a passenger is sitting in your car and it needs to deploy an airbag.
These sensors are located underneath the passenger seat (left) and if they aren’t working properly then you might get this warning message on your Mercedes dashboard.
6. Faulty Battery
The final common cause for this problem is a bad battery, sometimes when the battery goes dead, the warning light can come on as a false alarm and be mistaken for a problem with the airbag system.
The battery controls most electronics on your Mercedes Benz and if it is dead, then it will cause some of those electronics to malfunction.
In order to check this, you need to get a voltmeter and test the voltage of your battery while it is connected to the car. If it isn’t getting enough power, then there might be something wrong with the battery.
What to Do When “Front Left Malfunction” Comes Up On Your Dashboard?
The first thing I recommend is to try to reset your Mercedes, you can do this by using an OBD2 scanner to clear the fault codes or disconnecting the battery for about 5 minutes.
If it goes off then it’s probably a false alarm caused by the battery, if it doesn’t go off and you are still getting this fault message
Then it could be any of the causes mentioned above and I advise you to take your Mercedes to any qualified independent garage or the nearest Mercedes dealer to have it checked out.
Additional Sources
https://mbparts.mbusa.com/mercedes-c300-srs-malfunction
https://www.mersec.net/12/restraint_system.html
https://www.aclassclub.co.uk/threads/front-left-malfunction-consult-workshop.10776/
https://auto.howstuffworks.com/car-driving-safety/safety-regulatory-devices/seatbelt4.htm