Mercedes-Benz B250 ECM-Power Relay Replacement at your home or office.

Our mobile mechanics offer services 7 days a week. Upfront and transparent pricing.

Estimate price near me

Service Location

Customer Ratings

(5,730)

Included for free with this service

Online Booking

Mechanic comes to you

12-month / 12k-mile warranty

Free 50 point safety inspection

Our certified mobile mechanics can come to your home or office 7 days a week between 7 AM and 9 PM.

Customer Ratings

(5,730)

ECM-Power Relay Replacement Service

How much does a ECM-Power Relay Replacement cost?

On average, the cost for a Mercedes-Benz B250 ECM-Power Relay Replacement is $111 with $16 for parts and $95 for labor. Prices may vary depending on your location.

CarServiceEstimateShop/Dealer Price
2016 Mercedes-Benz B250L4-2.0L TurboService typeECM-Power Relay ReplacementEstimate$170.15Shop/Dealer Price$201.44 - $255.94
2015 Mercedes-Benz B250L4-2.0L TurboService typeECM-Power Relay ReplacementEstimate$150.15Shop/Dealer Price$181.47 - $235.99
2017 Mercedes-Benz B250L4-2.0L TurboService typeECM-Power Relay ReplacementEstimate$150.15Shop/Dealer Price$173.96 - $222.84
2013 Mercedes-Benz B250L4-2.0L TurboService typeECM-Power Relay ReplacementEstimate$150.15Shop/Dealer Price$181.43 - $235.92
2018 Mercedes-Benz B250L4-2.0L TurboService typeECM-Power Relay ReplacementEstimate$126.15Shop/Dealer Price$143.97 - $174.87
2014 Mercedes-Benz B250L4-2.0L TurboService typeECM-Power Relay ReplacementEstimate$150.15Shop/Dealer Price$181.47 - $235.99
Show example Mercedes-Benz B250 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.

Fast and easy service at your home or office

Backed by 12-month, 12.000-mile guarantee


Meet some of our expert Mercedes-Benz mechanics

Real customer reviews from Mercedes-Benz owners like you.

Excellent Rating

(5,730)

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

Joel

21 years of experience
987 reviews
Joel
21 years of experience
Mercedes-Benz C240 V6-2.6L - Brake Pads Replacement (Front, Rear) - Jacksonville, Florida
Very professional and kind, did an awesome job!

Efrain

20 years of experience
93 reviews
Efrain
20 years of experience
Mercedes-Benz CLK500 V8-5.0L - ABS Speed Sensor Replacement (Driver Side Front, Passenger Side Front) - Glenn Dale, Maryland
Great. Mechanic..Great. service Ken.

Chris

22 years of experience
2266 reviews
Chris
22 years of experience
Mercedes-Benz CL55 AMG V8-5.5L Turbo - Check Engine Light is on - Westminster, California
Very professional

Michael

21 years of experience
80 reviews
Michael
21 years of experience
Mercedes-Benz CLK320 V6-3.2L - Loss of power - Yelm, Washington
Works hard to figure out issues with your car to get it up and running safely

Excellent Rating

(5,730)

Rating Summary
5,332
192
54
29
123
5,332
192
54
29
123
Number of Mercedes-Benz services completed
63030+
services done by our mechanics
TOTAL NUMBER OF EXPERT Mercedes-Benz MECHANICS
1100+
experts on our platform

Recent articles & questions

How Does Hot Weather Affect Car Hoses?
Hoses Hoses are vital to the operation of your engine. They send vital fluids from one part to another. There are several critical systems under your hood that use hoses, but one of the most important (and most susceptible to...
The Best Used Cars to Buy If You’re Over Six Feet Tall
While While shorter than average drivers can have a tough time finding the right car, it’s equally hard for taller drivers, perhaps more so. If you’re feeling squished, or have to hunch over the wheel to drive, then you’re not...
P3485 OBD-II Trouble Code: Cylinder 11 Exhaust Valve Control Malfunction
P3485 means an issue with cylinder 11’s exhaust valve control circuit which causes sluggish acceleration and decreased fuel economy.

Getting random misfire code.

Your Chrysler sets a P0300 random or multiple misfire code when more than a 1.8% misfire rate is measured during two trips. Countless issues can set this code, from a vacuum leak to a bad coil pack. Your engine is...

Glow Plug System light comes on sometimes and engine has a lack of power when the light is on.

Hi there. Check the glow plug relay and see if its plugged in. Check the circuits to the glow plugs and see if there is power to them when the key is turned on. The circuit to the glow plugs...

Steering wheel Problem

Your vehicle is equipped with electric power steering. Failure of the steering wheel to return, and re-center itself, can be caused by vehicle misalignment (in particular, caster is off), damage to the suspension, or faults in the electric power steering...

How can we help?

Our service team is available 7 days a week, Monday - Friday from 6 AM to 5 PM PST, Saturday - Sunday 7 AM - 4 PM PST.

1 (844) 997-3624 · hi@yourmechanic.com