Mercedes-Benz Ignition Lock ESL Problems

Vehicle:   Mercedes-Benz
Difficulty: ⚫⚫⚫⚫⚪
DIY Cost: $150-$600
Est. Time: 3-4 hr

A common problem with Mercedes-Benz W204 C-Class, X204 GLK, 172 SLK, and 207, W212 E Class is the steering lock module failure which prevents the car from starting.  

When the steering lock fails the key still turns the ignition but it will not start the engine. Instead when the key is inserted in the ignition a message in the dash says "Please Remove Key". There is no sound from the steering lock that you normally hear when the ignition is unlocked. 

merced ezs emulator

Independent auto repair shops may install an emulator which bypasses the ignition lock. Installing an ESL emulator is not recommended by the manufacturer and will not be completed by any authorized Mercedes-Benz deaership. The recommended repair is to replace the ignition lock with a new unit. 

When installing an emulator the steering lock no longer works which can be a safety concern. 

You still need to have the emulator to be programmed to your car. 

mercedes ignition switch

You will need to send your ignition switch and a working key to a third party to get the emulator programmed. 

Symptoms

Once the ignition lock fails, the steering wheel won't unlock, and the car won't start. 

  • The key turns, but the engine won't start.
  • Take key warning on the dashboard.
  • Car starts intermittently
  • Steering wheel stuck
  • Can not unlock the ignition or steering wheel

What you will need

Procedure

In this guide, you will find instructions on how to remove the steering column and replace the steering column lock on a Mercedes-Benz C-Class (W204), E-Class ( C207 W212). 

  1. Turn the steering wheel so that the front wheels are pointing forward. Center the steering wheel. (If you can not unlock the steering wheel, skip this step. )
  2. Leave the key in position II. Dash lights on but engine off. (If the steering wheel is locked or the vehicle does not start, skip this step.) 
  3. Disconnect the battery and wait 15 minutes. 
  4. Remove the two T-25 bolts on the back of the steering wheel. removed airbag
  5. Unplug the electrical connectors for the airbag. disconnect airbag
  6. Remove the 10mm hex bolt that secures the steering wheel to the steering column. Counter hold the steering wheel to avoid putting pressure on the steering lock. remove steering wheel
  7. Mark the steering column and wheel with a marker so that you can reinstall the steering wheel in the same location. Use tape to prevent the clock spring from spinning. Remove the clock spring from the steering column. 
  8. Unplug the electrical connectors from the combination switch (turn signal, wiper switch). 
  9. Remove the four E-Torx bolts that secure the steering column to the dashboard. steering column bolts
  10. Remove one bolt near the Universal joint on the steering shaft, just above the brake pedal. steering shaft
  11. Unplug the electrical connectors from the steering wheel adjustment motors. At this point, the steering column should be free. Mercedes C300 won't start, remove and replace ignition lock
  12. Remove the steering column from the vehicle by pushing it down then pulling it out from under the dashboard. Getting the steering column out takes a lot of patience and trying. Due to the limited space, it will take several tries to get the steering column out. remove mercedes steering column
  13. Remove the 13mm nut that secures the ignition lock to the steering column. meredes wont start
  14. Press the bolt in and remove the ignition lock. If you were able to leave the ignition on in step 2, you would press the bolt in and easily remove the steering lock. If your ignition is locked, use an angle grinder to cut the bolt off. Then punch the reminder of the bolt in to press it and remove it from the steering column. 
  15. Install the new steering lock. 
  16. Reinstall the steering column in reverse order. Install new bolts.
  17. Torque the steering column bolts and steering wheel bolt to specs. 
  18. Program the new ignition lock to be able to start the car. 

We strontly recommend repairing the vehicle properly by replacing the ignition lock so that the safety and security features of the vehicle continue to work as designed. 

Torque Specs

  • The bolt that secures steering wheel to steering shaft: 80Nm

Programing Mercedes-Benz Ignition Lock

Whether you install a new steering lock or a steering lock simulator, it will need to be programmed. 

The emulator can be programmed with an OBD-II tool such as VCDI Programmer or CCDI Xhrose Programer. 

Should I install an ignition emulator? 

We see many cases where the ignition lock gets replaced with an emulator. 

It is important to understand that the steering wheel will no longer lock when an emulator is installed. This is a safety concern that you need to consider. 

Can I install a Mercedes emulator without removing the ignition lock? 

While not recommended, it is possible to install an emulator without removing the old ignition lock or steering column, but only if you can get the key to work at least once.

Once your original key is inserted in the ignition and unlocks the ignition, unplug the wire from the original ignition lock. You can reach the ignition lock by reaching under the dashboard to the back of the steering column. This leaves the old ignition lock in unlock position.

The wire harness that was disconnected gets connected to the new emulator, which needs to be programmed. 

Notes

  • Handle the airbag with care.
  • Keep your body at least 2 ft away from the airbag. 
By YOUCANIC Automotive Experts
Nov 2020
Mercedes-Benz Ignition Lock ESL Problems A common problem with Mercedes-Benz W204 C-Class, X204 GLK, 172 SLK, and 207, W212 E Class is the steering lock module failure which prevents the car from starting.