Got a Mercedes with the SRS light illuminated? Not sure why this is happening to your car?
An illuminated SRS points to a buggy airbag system that has several different components. Any one of the airbag system’s components could be causing the issue, requiring a quick repair or replacement.
I will go over the most common issues causing the SRS light on your Mercedes. Let us get started.
SRS malfunction – Mercedes car won’t start: What’s causing the issue
The SRS (Supplemental Restraint System) light in your Mercedes car could be due to the following:
- Problems with the seat belt latch
- Occupancy seat sensor malfunction
- Corroded SRS components or control unit
- A faulty airbag clock spring
I would not suggest that a beginner or casual DIYer fix these problems as SRS systems are complex and I would suggest that you rather let a professional handle the repairs or replacements, as the SRS system is extremely important (in the case of an accident) and can be very dangerous to the vehicle occupants if it malfunctions.
If any of the components fail to work properly after a DIY fix, it can cause issues in deployment, which is definitely not what we want to happen!
Let us look in detail at what could be causing the SRS light in your Mercedes to illuminate and how much it may cost you for repairs or replacements.
Problem with seat belt latch
SRS sensors detect whether a seat belt is fastened or not. Anything that could cause interference with it can result in the SRS light illuminating. There might be some blockage or dirt that needs removing.
You can use a thin screwdriver to feel inside the seat belt latch for any blockages. Doing so can also clear particles away from the sensor’s path. Make sure you are gentle to avoid damaging any component.
If there is too much dirt and the latch requires cleaning, buy a can of compressed air and spray it into the buckle.
Occupancy seat sensor malfunction
A Mercedes car comes equipped with different features, either for safety purposes or for efficiency.
The passenger seat comes with an auto-detect sensor that relays information to the control unit whether or not the seat is occupied. If it is not, the vehicle does not deploy any airbags.
The same is the case when you attach a Mercedes Benz child seat to it. The sensor detects the presence of a child seat using RFID and does not deploy airbags during an accident to ensure safety.
An easy way to diagnose if this is causing the issue is to check your dashboard. You should have the red SRS light with an additional orange airbag light illuminated.
To fix the problem, you need to check the different wires and connectors for wear and tear. To do that, you are required to remove the seat and the brake components (if any).
Your local mechanic can get it done for you. It is usually a 2-hour job and can cost up to $300.
Corroded SRS components or control unit
If you’ve been driving around during the wet season and got water in your Mercedes, the SRS components located under the seat can get wet. It causes corrosion.
You can also have a corroded SRS control unit. To check for corrosion, you would need to access the airbag module. It is usually located under the ashtray in a Mercedes. Take that out and examine the airbag system for corrosion.
Replacing the module will cost you upwards of $600 in parts alone.
For labor costs, since it is a quick job, add another $100 to $130 to the bill.
Faulty airbag clock spring
The electrical wires on an airbag system are found near other vehicle components. For protecting it, the car comes equipped with an airbag clock spring. This spring is located inside the steering wheel and protects the electrical wires during turning.
The cost of replacing the airbag clock spring is between $390 and $420, with an additional $100 to $120 for labor.
How to fix SRS light: Mercedes SRS reset tool
With so many common issues that could force the SRS light to come up on your Mercedes dashboard, a Mercedes SRS reset tool makes diagnosing the problem simpler and time-efficient.
A code reader can help you read and erase fault codes. However, you would need a mid-tier scan tool capable of accessing the SRS system. You can find a decent SRS OBD2 scanner for between $110 and $150.
Generally, the SRS light should go off after fixing the problem, but sometimes it might need a hard reset. A scan tool can help with that.
Here is how you do a hard reset on your SRS reset tool (make sure you fix the problems first before doing this!):
- Connect the SRS OBD2 scanner to the OBD2 port on your Mercedes.
- Turn the ignition but do not turn the engine on.
- Start by tapping on “read fault codes”.
- If you have fixed the problems, you can erase the fault code.
If you have not fixed the underlying issue, use the fault codes to determine the problem and fix it before you erase the codes.
How to fix SRS light: Should you DIY or visit a professional mechanic?
Generally, I would tell you some steps to follow for a quick DIY repair or replacement. However, with the SRS system, car owners should not take any risks conducting repairs themselves, even if they like to do things themselves and would ordinary DIY – please rather don’t!
SRS is responsible for deploying airbags in an emergency or accident, and if your repairs are not perfect, this can affect its deployment. Do not risk your life or your family’s life to save a few bucks with DIY repairs.
SRS malfunction Mercedes car won’t start
An SRS malfunction can happen to any car, and there is no need to panic!
When you turn on the ignition and are greeted with an SRS light, you can still turn the engine over and drive (although I don’t recommend it since it is not safe). However, there might be a situation where your SRS light illuminates but the car won’t start.
A dead car battery or battery which is almost depleted could be the reason for the SRS light to come up but the car won’t start. Investing in a Mercedes SRS reset tool is a great way to diagnose the underlying issue, save time and money.