So this owner was complaining about an unusual problem with his car - a Mercedes Benz c300 2016 model - which was that the radio was not working. He required my services to resolve the problem.
Upon confirming his complaint, I got right to work, performing basic electrical system tests. Every circuit appeared to be in good working order. I promptly plugged in my diagnostic computer to interrogate the various control modules in the car.

One of the error codes indicated a problem with the vehicle's main battery, which I quickly resolved using the Mercedes workshop and engineering menu(aka hidden menu).

What is this Mercedes ‘Hidden’ menu?
Most Mercedes-Benz owners are unaware of a menu in their automobiles that allows them to quickly assess the vehicle's condition. It's no coincidence that it's dubbed the ‘hidden’ menu.
Simply put, it is a menu that can actually help you access some features that you would otherwise require a diagnostic computer for.

The 'hidden' menu holds various features, but the three most important of these from my experience are:
1. Reset your service counter - which is a standard procedure after every routine maintenance.
2. Deactivate your electric parking brakes, when you want to do pad replacement. This is especially for vehicles that have electric parking brakes.
3. Check vehicle info like the onboard electrical system which is what I used it for in my case.

How to access the Mercedes ‘Hidden Menu’
I guess now the question you may be asking is, “how can I access this hidden menu?”
The answer is dependent on the model and year of your Mercedes. The process is generally the same for most models from 2010 and up.
Regarding the model I worked on, the Mercedes Benz C-300 2016 model, here is how you can access the hidden menu:

1. Turn your key to stage 1 ignition.
2. Change the dash display to the main odometer (current miles / total miles) by repeatedly pressing the ‘back button’, which is normally placed on the left side of your steering wheel.
3. Press and hold the 'OK' button on the left and the ‘phone pickup button’ on the right of the steering wheel together for 3 to 5 seconds - This might be tough as you could get a prompt to reset your odometer, but a foolproof method is to first press the call button before the okay button.

If you followed the instructions correctly, you should see the Mercedes workshop and Engineering menu (also known as the hidden menu) displayed on your instrument cluster.
Thank you for taking the time to read this far. I only hope that was informative enough.


Not forgetting the problem with our C300; after numerous tests and diagnosis, we determined that the radio unit had gone bad and needed to be replaced.


DISCLAIMER:This post is intended to be educational only. I always recommend that you hire an experienced technician to inspect your car, especially for electrical problems you may not understand.

Ejike Odoh, Mercedes benz specialist based in Lagos, and writer of mercedes benz related topics.
Call or WhatsApp 08156245496 for issues related to your Benz automobiles.

Lovely

aycapri:
Lovely

Thank you

Story. U still be kazeem. Nairaland business man. Ole