Mercedes-Benz C400 Car Door Lock Relay Replacement at your home or office.

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Car Door Lock Relay Replacement Service

How much does a Car Door Lock Relay Replacement cost?

On average, the cost for a Mercedes-Benz C400 Car Door Lock Relay Replacement is $135 with $40 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2015 Mercedes-Benz C400V6-3.0L TurboService typeCar Door Lock Relay ReplacementEstimate$195.63Shop/Dealer Price$233.29 - $306.90
Show example Mercedes-Benz C400 Car Door Lock Relay Replacement prices

What is the Door Lock Relay all about?

Power door locks used to be a luxury feature on vehicles, but they've become so mainstream that nearly every vehicle is now equipped with them. The lock’s function is to make securing your vehicle, as well as passengers, simple and easy. Instead of reaching across the vehicle to lock or unlock the doors, it can be done by simply pressing a button. Pressing the button completes a circuit, enabling the lock actuator to receive power which activates the locking mechanism to the desired position. The circuit is routed through a door lock relay, which acts as a switch to direct the power to actuators on the door locks. When unlock is pressed, the door lock relay switches from a neutral position to activating a pulse of power to the unlock circuits on the actuators. When the lock button is pressed, a pulse of power is switched to the lock circuit of the actuator to lock the doors. When the relay for the door locks is not working properly or sticking, either the lock function, the unlock function, or both are inoperative.

Keep in mind:

  • When service is performed on any electrical system, the battery should be disconnected to prevent accidental damage or injury.
  • If the door lock relay needs to be replaced, it can be indicative of an underlying concern with the power door locks.
  • Some vehicles equipped with remote keyless entry will find the key fob operates the driver’s door lock even while the door lock relay is defective.

How it's done:

  • Test the operation of electric door locks.
  • Test the fuse for that circuit.
  • Test the relay.
  • Replace the faulty relay.
  • Test for proper operation of electric door locks.

Our recommendation:

If you are experiencing problems with your power door locks, have one of our expert technicians diagnose and repair the system. Relays and electrical systems can be complex, and a broken wire or door lock actuator problem can easily mimic the symptoms of a door lock relay and vice versa.

What common symptoms indicate you may need to replace the Door Lock Relay?

  • Power door locks don’t lock when you press the button, while the unlock feature works.
  • Neither the lock nor unlock functions work.

How important is this service?

Power door locks are a convenience feature on your vehicle. If the power locks aren’t working, you can use the key to unlock your door and the locks can be manually operated as well. Have the power door lock system repaired at your convenience.

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Excellent Rating

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Rating Summary
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5,298
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Nazareth

27 years of experience
289 reviews
Nazareth
27 years of experience
Mercedes-Benz C400 V6-3.0L Turbo - Car Battery Replacement - Glendora, California
He was very fast and his prices are extremely reasonable

Charles

34 years of experience
342 reviews
Charles
34 years of experience
Mercedes-Benz C400 V6-3.0L Turbo - Back To School Promo - Austin, Texas
He has done a great job in the timely manner. I would definitely recommend him.

Jose

20 years of experience
84 reviews
Jose
20 years of experience
Mercedes-Benz CLK350 V6-3.5L - Battery - Miami, Florida
Great work !!!!

Raul

34 years of experience
285 reviews
Raul
34 years of experience
Mercedes-Benz S320 L6-3.2L - Trunk Latch Adjustment - Berkeley, California
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Excellent Rating

(5,692)

Rating Summary
5,298
192
54
28
120
5,298
192
54
28
120
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