Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. How to Replace an Electronic Control Relay

How to Replace an Electronic Control Relay

common automotive relay

Electronic relays are used throughout your vehicle. They control everything from electric windows to the electric fuel pump. They are used as a low-voltage trigger for high voltage consuming components. By only triggering components as needed, relays help your vehicle conserve energy. Since the internals of a relay are both electronic and mechanical, think of it as a switch that uses electricity to “switch” itself on. This in turn switches on the component it controls. If one of the electronic components in your car is not working, it is possible that it is time for a new electronic control relay.

Part 1 of 1: Replacing the electronic relay

Materials Needed

common interior fuse relay panel location

Step 1: Locate the relays. With the increasing amount of electronics in modern vehicles, it is possible your vehicle may have more than one fuse/relay box.

There can be multiple locations underhood as well as inside the passenger compartment or trunk.

pulling out the relay

Step 2: Replace the faulty relay. With the key in the off position, remove the faulty relay.

It should simply unplug by hand. Set the faulty relay aside.

Insert the new relay in the correct position. Use as little force as required to remove and install relays as automotive wiring and connectors can be delicate and brittle with age.

  • Note: Older vehicles may have relays mounted to the firewall or inner fender well. Consult your owner’s manual or shop manual for exact locations.

firewall mounted relay

Step 3: Verify the repair. Turn the key to the on position or start the vehicle to verify the component that the relay was for is functioning properly.

Once verified, replace any covers or panels you removed for access.

Because they control many different parts of the car, it can be difficult to tell whether or not your issue is caused by a bad electronic control relay. If you need a diagnosis or relay replacement for your vehicle, contact YourMechanic today to arrange for a mobile technician to come to your home or office.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...


Related questions

Q: Car won't crank like theirs no gas.

The car's ability to crank over does not depend on whether or not it has gas in the tank. Since the dash lights light up, this suggests you have power so we can rule out the fact that there is...

Q: Left turn signal malfunction.

Check the bulb contacts, front and rear, and just make sure there is no obvious corrosion. Check the headlight harness connection to the headlight bulbs as well. From what you are describing, there is some sort of short or voltage...

Q: Heater blower stuck on high and will not turn off unless igniton is off

This suggests that the relay may be supplying power to the blower motor regardless of turning the switch off. The blower motor relay supplies power to this motor when you turn the switch to "on" that can sometimes fail. When...