Reasons Behind Ignition Lock & Tumbler Failure in Your Mercedes

Over time in your Mercedes Benz, your vehicle’s key may begin to stick and eventually not turn, or the ignition lock/tumbler system will stop starting the engine. The term ignition lock cylinder is basically a fancy term for the keyhole that we use to power up the car. The issue of ignition lock and tumbler failure tends to be more common in older Mercedes models because many newer models use keyless entry and push-button start and keyless power starting system.

Mercedes Benz vehicles are known for durability and longevity, and a failure within the ignition lock and tumbler oftentimes will come down to lack of maintenance of the vehicle. Although it is alarming when your vehicle’s engine won’t start, it is possible that it is simply due to an ignition lock failure and not a severe mechanical problem. Knowing to properly maintain your Mercedes is important in avoiding issues with your ignition lock and tumbler.

What Function do the Ignition Lock and Tumbler Serve?

The ignition lock cylinder is comprised of the tumbler and key assembly necessary to start your Mercedes. When a key is entered into a tumbler, it will also provide the power to other vehicle systems such as the radio, your vehicle’s ECU (Engine Control Unit), and the fuel and HVAC (Heating, Ventilation, and Air Conditioning) systems. Since the ignition lock cylinder and tumbler are so closely linked to a number of vehicle functions, it is likely that you will experience a variety of issues when the ignition lock and tumbler begin to fail.

Recognizing Ignition Lock Cylinder and Tumbler Failure

Generally speaking, a vehicle that is beginning to experience a faulty ignition lock will show symptoms early on, which is why it is important to be able to recognize all signs and symptoms involved with ignition lock and tumbler failure. The most common sign that your ignition lock is beginning to fail is if you are struggling to power on the vehicle. Since we are using the ignition lock and tumbler every time we start and turn off our Mercedes, it is of no surprise that this extensive use may cause some wear on that aspect of our vehicle. A worn ignition lock will simply not function correctly when the key is inserted and may include issues in other key positions. There may be a number of key positions that require some movement in order for them to function correctly, and these issues will generally worsen over time, causing a full ignition lock failure.

Other common signs of ignition lock failures include difficulty inserting or removing the key from the tumbler and/or the complete inability to start the vehicle. As the ignition lock cylinder wears out over time, the worn cylinder may jam up the key when inserted, turned, or removed from the tumbler. This jamming or binding of the key will eventually lead to the inability to start or power on the vehicle.

Since the ignition lock cylinder is connected to the electronic ignition switch, if the ignition lock cylinder is unable to turn to the power position, then it will not be able to engage with the electronic ignition switch. This is often referred to as a no-start condition and can be caused by issues beyond the ignition lock and tumbler, so it is important to get a proper diagnosis if you are experiencing this problem.

Reasons for Ignition Lock and Tumbler Failure

The most prevalent reason the ignition lock and/or tumbler will begin to fail in your Mercedes is due to daily use causing wear and tear. There is a possibility that debris could be obstructing the key from turning properly, but it is much less common than the tumbler simply beginning to be worn down.

If you own an older Mercedes model, it is not unlikely that you will have to replace the ignition lock cylinder due to it being worn out. It is often suggested that a preemptive replacement be done to avoid the inconvenience of complete ignition lock cylinder failure. It is easy to ask about the ignition lock cylinder when you bring your car in for routine maintenance and/or repairs if you suspect it is wearing out.

Trust the Professionals

When considering replacing the ignition lock and tumbler in your Mercedes, or if you have any questions about other aspects regarding your vehicle, it is best to contact a trusted mechanic and/or specialist to get the best advice. If you live in or around the Dallas, University Park, Highland Park, Irving, or Coppell, TX areas, consider contacting Louden Motorcar Services regarding ignition lock and tumbler issues in your Mercedes.

* Mercedes Benz Car image credit goes to: joephotographer.