Mercedes-Benz 400E 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 400E Electronic Control Relay Replacement is $141 with $46 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1993 Mercedes-Benz 400EV8-4.2LService typeElectronic Control Relay ReplacementEstimate$207.35Shop/Dealer Price$247.94 - $330.34
1992 Mercedes-Benz 400EV8-4.2LService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
Show example Mercedes-Benz 400E 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

(5,730)

Rating Summary
5,332
192
54
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5,332
192
54
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Ryan

5 years of experience
60 reviews
Ryan
5 years of experience
Mercedes-Benz 400E V8-4.2L - Power Steering Pump - Phoenix, Arizona
ryan was good but you service was nasty ,and i will never used you all again. I was a good customer and i spend money with you for over 3 years and i never thought i would get that kind of service..

Chris

22 years of experience
2266 reviews
Chris
22 years of experience
Mercedes-Benz CLS500 V8-5.0L - Oil Change - Corona Del Mar, California
Chris was great. He explained everything and tried to save me as money as he could.

James

31 years of experience
705 reviews
James
31 years of experience
Mercedes-Benz ML350 V6-3.0L Turbo Diesel - Oil Change - Tustin, California
I was a bit worried having my MB ML 350 Bluetec worked on, but James did a great job and I would use him again.

Napoleon

27 years of experience
147 reviews
Napoleon
27 years of experience
Mercedes-Benz S550 V8-5.5L - Check Engine Light is on - Norwalk, California
Napoleon arrived early (no prob). I'm a first time user of this service and had a great experience. Napoleon is a down to earth guy. He explains things well and answered any and all questions/concerns that I had. He diagnosed the issue and explained what happened to my baby. I will recommend this service to all my family and friends. Thanks

Excellent Rating

(5,730)

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