Ask a Mechanic: A new steering wheel not needed to replace a broken button

Dear Ask a Mechanic,

I have a 2017 Mercedes E300 4matic. When I brought it to be serviced last year, I was told the OK button on the left side of the steering wheel was broken, so the service reminder could not be reset.  I was told that to fix it, I would have to replace the whole steering wheel. I can, however, change the message by pressing the home button. My question is if it is true that the whole steering wheel needs to be changed or can just the button be replaced? – Busted Benz

There are all kinds of maintenance reminder systems out there. There is the simplest, user-defined mileage and time counter found in many Hyundai models and the more complex oil-life monitors, which also consider operating conditions, that are common in many domestic vehicles. Others, such as those in Hondas and BMWs, track and call-out multiple maintenance items.

Mercedes has had several comprehensive service reminder and tracking systems in its vehicles for quite some time now. One thing that has been common to all the ones I’ve encountered is that they’re able to be reset through some combination of pressing instrument cluster or steering wheel buttons. This is true of your E-Class, too.

Your unusual situation raises two questions. First is if you must replace the entire steering wheel to rectify the one faulty switch? And second, can the maintenance system be reset without fixing the broken switch? Thankfully, as you provided your vehicle’s VIN, I was able to make some specific inquiries.

Regarding the first question, no you do not have to replace the entire steering to replace the switch. The Mercedes parts dealer I use shows the switch is available as a separate item, costing under $300 (installation would be extra). I did not price an entire new steering wheel but replacing it would cost considerably more.

As to the second question, Mercedes-Benz Canada’s technical service team did confirm that the system in your E300 can be reset using Mercedes’ diagnostic tool. Obviously, few, if any, independent shops will own a Mercedes scan tool, so that pretty much means going to a dealership to have the vehicle serviced.

Could an aftermarket tool perform the reset? Perhaps. My Autel scan tool, for instance, often shows it as an option, but I am not sure whether it will work with your Mercedes model. Either way, you do have options that don’t involve getting a new steering wheel or having to live with the reminder messages always appearing.

Ask a Mechanic is written by Brian Early, a Red Seal-certified automotive technician. You can send your questions to wheels@thestar.ca. These answers are for informational purposes only. Please consult a certified mechanic before having any work done to your vehicle.