Mercedes-Benz C400 Electronic Control Relay Replacement at your home or office.

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Electronic Control Relay Replacement Service

How much does a Electronic Control Relay Replacement cost?

On average, the cost for a Mercedes-Benz C400 Electronic Control Relay Replacement is $151 with $46 for parts and $105 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2015 Mercedes-Benz C400V6-3.0L TurboService typeElectronic Control Relay ReplacementEstimate$217.35Shop/Dealer Price$255.14 - $335.44
Show example Mercedes-Benz C400 Electronic Control Relay Replacement prices

What is the Electronic Control Relay all about?

A wide range of electronic systems must work properly in order for the vehicle to operate. That means there is a need for several different controllers to ensure proper operation. One of the most important is the electronic control relay. You might be more familiar with the term “main relay” because of its role in vehicle performance.

The electronic control relay operates the fuel pump and sends power to the engine’s injectors. Without the main relay, fuel will not flow from the tank to the engine, and your injectors will not atomize gasoline into the combustion chamber. In short, your car wouldn’t run. Electronic control relays are subject to failure from a number of different problems, including outright failure, heat damage, cracked solder and more.

Keep in mind:

  • The electronic control relay may not operate, or may operate intermittently depending on the source of the trouble.
  • A number of other problems can masquerade as a main relay failure, so it’s vital that you have one of our expert mechanics diagnose the issue.

How it's done:

  • The electronic control relay is located and accessed then verified it needs replaced
  • The defective relay is removed from the vehicle
  • The new electronic relay is installed
  • The components that the electronic relay operates are checked for proper operation
  • The vehicle is road tested for proper operation

Our recommendation:

Traditional turnkey ignition the relay will click three times during the starting process. If you listen closely, you should hear a single click when you turn the ignition to “on”. You should hear another when the Check Engine light turns off. Finally, there should be a third click when you turn the key to the “start” position. If you do not hear a click at any of these three points, there may be a problem with the electronic control relay. Have one of our expert mechanics diagnose and replace the relay if required.

What common symptoms indicate you may need to replace the Electronic Control Relay?

  • Engine doesn’t start, especially in cold weather
  • Engine may not start a few minutes after turning it off
  • No sound from the fuel pump when the ignition key is turned to “On”

How important is this service?

Given the fact that the electronic control relay powers the fuel pump and your fuel injectors, it is essential to replace a faulty one. However, many other problems can present similar symptoms, so it’s very important to have the issue diagnosed by one of our expert mechanics.

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Excellent Rating

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Rating Summary
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5,332
192
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Nazareth

27 years of experience
294 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.

Andrew

14 years of experience
113 reviews
Andrew
14 years of experience
Mercedes-Benz C300 V6-3.5L - Car is not starting - Puyallup, Washington
Showed up on time and was very friendly and professional. Got my vehicle up and running in no time. Would definitely use his services again and highly recommend him to anyone needing a mechanic.

Kwante

12 years of experience
53 reviews
Kwante
12 years of experience
Mercedes-Benz C300 V6-3.0L - Ignition Coil - Gwynn Oak, Maryland
he was very knowledgeable, courteous and very thorough on diagnosing and repairing my vehicle. I would recommend him to anyone else that needed work done to their vehicle. As a matter of fact I recommend him to my son who drives a Chrysler minivan, who in turn, immediately booked Mr. Stokes by appointment to get work done to his minivan.

Excellent Rating

(5,730)

Rating Summary
5,332
192
54
29
123
5,332
192
54
29
123
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