Mercedes-Benz ML400 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 ML400 Electronic Control Relay Replacement is $141 with $46 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2015 Mercedes-Benz ML400V6-3.0L TurboService typeElectronic Control Relay ReplacementEstimate$207.35Shop/Dealer Price$247.94 - $330.34
Show example Mercedes-Benz ML400 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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Ryan

18 years of experience
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Ryan
18 years of experience
Mercedes-Benz C230 L4-1.8L Turbo - Spark Plugs - Ogden, Utah
Amazing got everything done in under 2 hours very good

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19 years of experience
554 reviews
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19 years of experience
Mercedes-Benz C300 V6-3.0L - Oil Change - Houston, Texas
Very professional

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10 years of experience
35 reviews
Brandon
10 years of experience
Mercedes-Benz S500 V8-5.0L - Oxygen Sensor Replacement (Front/Upper/Upstream) - Bellevue, Washington
On time. Very professional and knowledgeable. Great advice given for follow up repairs and regular maintenance. Will definitely use him for future repairs and recommend to friends and family.

Vaughan

11 years of experience
92 reviews
Vaughan
11 years of experience
Mercedes-Benz C300 V6-3.0L - Pre-purchase Car Inspection - Irving, Texas
Vaughan was extremely helpful and professional with my pre-purchase inspection. I highly recommend his services.

Excellent Rating

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Rating Summary
5,278
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119
5,278
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