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

CarServiceEstimateShop/Dealer Price
1992 Mercedes-Benz 300SDL6-3.4L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$207.35Shop/Dealer Price$247.94 - $330.34
1979 Mercedes-Benz 300SDL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
1980 Mercedes-Benz 300SDL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
1984 Mercedes-Benz 300SDL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.93 - $310.32
1982 Mercedes-Benz 300SDL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$228.00 - $310.44
1978 Mercedes-Benz 300SDL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$187.35Shop/Dealer Price$227.97 - $310.39
1993 Mercedes-Benz 300SDL6-3.4L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$192.35Shop/Dealer Price$232.73 - $314.97
1981 Mercedes-Benz 300SDL5-3.0L Turbo DieselService typeElectronic Control Relay ReplacementEstimate$192.35Shop/Dealer Price$233.39 - $316.11
Show example Mercedes-Benz 300SD 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

(7)

Rating Summary
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Braxton

11 years of experience
205 reviews
Braxton
11 years of experience
Mercedes-Benz 300SD L5-3.0L Turbo Diesel - Car is not starting - Orlando, Florida
Very kind and helpful. Fast service and very courteous.

Robert

31 years of experience
641 reviews
Robert
31 years of experience
Mercedes-Benz 300SD L5-3.0L Turbo Diesel - Noise from engine or exhaust - Mountain View, California
Robert is good or even better than the other reviews. He does not only solve your problem but he ensures that your car is at its best before he leaves. He tries very hard to make your car perfect. When parts are not available he will try to make it. I regret very much not to hive him a tip when he left. It seems that Robert has a very busy schedule. Perhaps, his devotion to perfection takes extra time and make him a little bit late on schedule.

Rocco

22 years of experience
302 reviews
Rocco
22 years of experience
Mercedes-Benz 300SD L5-3.0L Turbo Diesel - Brake Pads Replacement (Front) - Newport Beach, California
Rocco was fantastic!

Jim

33 years of experience
193 reviews
Jim
33 years of experience
Mercedes-Benz 300SD L5-3.0L Turbo Diesel - Coolant is leaking - San Ramon, California
Identified the problem immmediately

Excellent Rating

(7)

Rating Summary
6
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1
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6
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Number of Mercedes-Benz 300SD services completed
77+
services done by our mechanics
TOTAL NUMBER OF EXPERT Mercedes-Benz MECHANICS
1100+
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