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Why is my Mercedes-Benz not starting?

Mercedes-Benz Start Failure Troubleshooting Guide

One of the biggest frustrations in the automotive life is when one’s vehicle simply will not start. Taking the ride into a shop is sometimes a necessity, but there are a variety of tests one can perform at home to see if the issue can be easily remedied. What steps can you take if your Mercedes-Benz won’t start?


If a maintenance appointment is necessary, we recommend our certified service center!


We’ve compiled some common spots to check for issues in your Mercedes-Benz below. These can apply whether your engine clicks but doesn’t start, or if it dies after starting, or if the car turns over but won’t start, or if the key won’t even turn in the ignition. The point is, your Mercedes-Benz is not starting, and the issue could lie in one of the categories below.

We don’t have room to go into a lot of detail on each of the categories below here, but if you check these areas and find your problem, you’ll have an idea of what your next Google search should be.

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2020 Mercedes-Benz GLA 45 under the hood

Systems to Check to Troubleshoot a Mercedes-Benz Starting Issue

  1. Verify the battery is fully charged
  2. Check fuses and relays, such as the starter circuit, ignition, EIS and fuel pump
  3. Check the gear selector/brake light switch
  4. Check the fuel pressure
  5. Use a scanner to check engine fault codes
  6. Check the starter motor
  7. Check the ignition system, spark plugs and coils
  8. Check the crankshaft position sensor
  9. Check the key fob battery and Driver Authorization System

Other issues preventing start can include ECM / PCM computer failure electrical problems, or issues with the camshaft position sensor, shifter selector module, or the driver authorization or immobilizer device.

What’s required for a Mercedes-Benz to start properly?

To start properly, several elements in a Mercedes-Benz must be functioning. The vehicle needs fuel, a spark, electrical power to crank the engine, and a functioning Drive Authorization System.

If things are really not working out, you could always order a new Mercedes-Benz.