Mercedes-Benz SL400 ECM-Power Relay Replacement at your home or office.

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ECM-Power Relay Replacement Service

How much does a ECM-Power Relay Replacement cost?

On average, the cost for a Mercedes-Benz SL400 ECM-Power Relay Replacement is $111 with $16 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2015 Mercedes-Benz SL400V6-3.0L TurboService typeECM-Power Relay ReplacementEstimate$146.15Shop/Dealer Price$171.44 - $207.94
2016 Mercedes-Benz SL400V6-3.0L TurboService typeECM-Power Relay ReplacementEstimate$126.15Shop/Dealer Price$151.47 - $187.99
Show example Mercedes-Benz SL400 ECM-Power Relay Replacement prices

What is the ECM-Power Relay all about?

Vehicle development has evolved over the past several decades to a point where it seems every vehicle function is controlled by a computer, right down to the engine itself. This is actually the case for the engine and its related functions as it is controlled by the engine control module, or ECM. The ECM monitors and adjusts operation and power distribution to the fuel supply and injection systems, engine timing, exhaust gas recirculation, emissions, ignition system, and several other systems. In order to dispense power to operate these other systems, the engine control module requires power itself.

The power distribution center, or fuse block, located under the hood houses most or all of the vehicle’s fuses and relays. It contains a relay for the ECM that is powered up when the ignition key is turned to the on position. This ECM power relay acts as a switch that supplies power to the ECM. When the ignition is turned off, power switches inside the ECM relay and it no longer receives battery power. If the ECM power relay stops switching as it should, you will experience vehicle problems. When the relay is stuck open, no power will be delivered to the engine control module and the vehicle won’t start. If the relay is stuck closed, constant power will be sent to the ECM even with the engine turned off and the battery will drain.

Keep in mind:

  • The battery should be disconnected any time the electrical system is being serviced.
  • There are several problems which can cause your vehicle not to start, with the ECM power relay being one of them. Have the problem diagnosed by one of our expert technicians.

How it's done:

  • The ECM-power relay is verified that it needs to be replaced. The relay is located in the engine main fuse relay control box.

  • The defective ECM-power relay is removed from the control box by pulling it straight up and out of socket.

  • The new ECM-power relay is installed into the socket and the engine scanned for codes.

  • The engine is started and the ECM-power relay is tested for proper operation.

  • The vehicle is road tested for proper operation of the ECM-power relay and is then checked for codes.

Our recommendation:

The ECM power relay should last the lifetime of your vehicle unless there is a power distribution problem or moisture that causes it to fail. If your vehicle won’t start, have one of our expert technicians diagnose the problem and replace the ECM power relay if necessary.

What common symptoms indicate you may need to replace the ECM-Power Relay?

  • Engine will not start when the key is turned.
  • Engine doesn’t turn over when ignition is on.
  • Check Engine light is on.
  • Battery drain which may leave it weak or dead.

How important is this service?

Although it is extremely unlikely the ECM relay will cause your vehicle to stall or create a safety concern, your vehicle may not start or the battery may die while the ignition is off. In either case, you will need to replace the ECM relay.

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David

10 years of experience
172 reviews
David
10 years of experience
Mercedes-Benz SL400 V6-3.0L Turbo - Pre-purchase Car Inspection - Orlando, Florida
Pre-Purchase service - On time with appointment. Follow up call and report was generated immediately which is greatly appreciate. Many thanks!!

Joel

21 years of experience
987 reviews
Joel
21 years of experience
Mercedes-Benz CLS500 V8-5.0L - Power Steering Fluid Service - Jacksonville, Florida
Awesome and knowledgeable mechanic! Will request again.

Ben

41 years of experience
1458 reviews
Ben
41 years of experience
Mercedes-Benz C230 V6-2.5L - 78,000 Miles Maintenance Service - Houston, Texas

Herman

13 years of experience
86 reviews
Herman
13 years of experience
Mercedes-Benz C300 V6-3.0L - Car is not starting - Hialeah, Florida
He was very informative and a good mechanic. I highly recommend him.

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