Mercedes-Benz 300D 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 300D Electronic Control Relay Replacement is $141 with $46 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
1978 Mercedes-Benz 300DL5-3.0L DieselService typeElectronic Control Relay ReplacementEstimate$207.35Shop/Dealer Price$247.94 - $330.34
1984 Mercedes-Benz 300DL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
1977 Mercedes-Benz 300DL5-3.0L DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
1993 Mercedes-Benz 300DL5-2.5L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.93 - $310.32
1980 Mercedes-Benz 300DL5-3.0L DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$228.00 - $310.44
1983 Mercedes-Benz 300DL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
1985 Mercedes-Benz 300DL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$192.35Shop/Dealer Price$232.73 - $314.97
1991 Mercedes-Benz 300DL5-2.5L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$192.35Shop/Dealer Price$233.39 - $316.11
Show example Mercedes-Benz 300D 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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Meet some of our expert Mercedes-Benz mechanics

Real customer reviews from Mercedes-Benz owners like you.

Excellent Rating

(14)

Rating Summary
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Ricardo

14 years of experience
339 reviews
Ricardo
14 years of experience
Mercedes-Benz 300D L5-3.0L Diesel - Brake Pads Replacement (Front, Rear) - Rancho Palos Verdes, California
Very courteous. Took care to explain every issue he encountered.

Jean

15 years of experience
92 reviews
Jean
15 years of experience
Mercedes-Benz 300D L5-3.0L Turbo Diesel - Car is not starting Inspection - Tampa, Florida
Jean did an excellent job Showed up early He did Above and beyond Service

Kiri

20 years of experience
372 reviews
Kiri
20 years of experience
Mercedes-Benz 300D L5-3.0L Diesel - Pre-purchase Car Inspection - Philadelphia, Pennsylvania
Kiri was very responsive and was available by text and phone as well. Thank you!

Tabitha

17 years of experience
336 reviews
Tabitha
17 years of experience
Mercedes-Benz 300D L5-3.0L Turbo Diesel - Oil Change - San Diego, California
Tabitha arrived earlier than the scheduled time and get the work done in no time. Very professional and I will ask for her the next service comes .

Excellent Rating

(14)

Rating Summary
13
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0
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1
13
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Number of Mercedes-Benz 300D services completed
154+
services done by our mechanics
TOTAL NUMBER OF EXPERT Mercedes-Benz MECHANICS
1100+
experts on our platform

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