Your turn signal is an incredibly important safety feature in your vehicle; however, it is one of the most overlooked features a vehicle has. But what about when the feature you take for granted isn’t working anymore?
Well, you dig into how the blinkers work! And, once you start digging, one of the first components you’ll come across is the turn signal relay.
How do you know if the turn signal relay is functioning correctly, and how much of a hit to your pockets are you going to see if you need to replace it? We’ll answer those questions and more for you here!
What is a Turn Signal Relay?
The turn signal relay – sometimes called the flasher relay – is the component that causes your turn signals to turn on and off each time you turn on a turn signal or push the hazard switch.
The turn signal relay is an electrical component that functions as a relay, turning on and off in a constant cycle whenever the button is depressed.
The turn signal relay is what you hear when you hear the clicking sound anytime one of these components is on.
Where is it located?
The location really depends on the vehicle you are driving. On most vehicles, you will find your turn signal relay located in the junction box or fused power distribution box with the other relays.
Some vehicle manufacturers create a guide on the fuse box cover that tells you what each relay does, while others require you to look in the owner’s manual
Some vehicle manufacturers (ie, Toyota and Lexus) make it complicated to get to the relay by requiring removal of a kick panel located near the steering column, but you can confirm the location by using a factory service manual.
Symptoms of a Bad Turn Signal Relay
Just because you know where something is and its function, does not mean you are able or ready to go ahead with the replacement. Below, we decided to outline three common and most likely signs that could suggest your turn signal relay needs to be replaced.
Again, while we listed three common symptoms of a bad turn signal relay here, we should really emphasize that if your turn signal blinks too fast, it is probably causing another issue causing the problem other than just the turn signal relay.
#1. Turn signal or hazards stop working.
By far, the most common symptom of a bad turn signal relay is that your turn signals or hazards no longer function properly.
As the job of a turn signal relay is to tell the turn signals to turn on, it only makes sense that if this component fails, there are going to be feature losses.
Additionally, if the relay fails in a mode in which it will not open any longer, or if a piece breaks off, causing an open circuit. Therefore, neither the turn signals nor the hazards will operate.
#2. The turn signal or hazards will not turn off.
While it is likely the turn signal or hazards lose function is the most typical indicator of a bad turn signal relay, that does not imply it is the only indicator.
A possible indicator is if you cannot get the turn signals or hazards to turn off. This occurs once a turn signal relay fails in the “on” position.
This is not likely the case because it would have to fail in such a way that the relay would become “closed” instead of a piece breaking off, as it is more likely to fail, although it could occur.
#3. Other lights malfunction.
While it is by far the least likely indicator of a broken turn signal relay, as any mechanic can tell you, electrical issues can cause strange malfunctions.
When we use the term strange, we should probably use wired instead, because these types of issues can occur due to shorts, wires crossed, or just about a dozen different issues possible with electrical malfunctions.
When this occurs, the current is going where it should not, and can create a wide variety of abnormal experiences.
If you are banging your head against the wall trying to troubleshoot an electrical issue. Test the relay anyway and get one more thing ruled out.
Turn Signal Relay Replacement Cost
If you have learned your vehicle needs a new turn signal relay you can take comfort in the fact that it is usually not a huge expense.
If you are going to take it to a professional mechanic, you can expect to spend from $60 to $120, and most of that is typically going to be the cost of parts.
That is why, if you are willing and able to replace the relay yourself, you are still going to spend approximately $30 to $60 in parts alone. That said, since the relay is an easier component to replace, you can save yourself some money by completing the replacement yourself.
While you can usually find inexpensive 3rd party flasher relays in the $15 range on Amazon and eBay, you would be better off spending a little more to ensure that you get the correct OEM replacement.
How to Test a Turn Signal Relay
There are a few different ways to test a turn signal relay, and we’ll summarize the top three here for you.
#1. Swap the Relay.
When you look at the turn signal relay, one of the first things vehicle owners notice is that it is one of multiple relays that look identical in that area. Nine times out of ten, the relays look the same, and they are the same.
Double-check the part numbers; if they match, simply swap relays. If the problem “migrates” to another area of your vehicle, then the turn signal relay has failed.
This is the simplest way to check for a bad turn signal relay, and it is essentially foolproof.
#2. The 6-Volt Test.
Again, this method is not foolproof, but it will find generally 95% of issues. You simply need a six-volt battery, and you will need to remove the relay from the vehicle. Connect the six-volt battery to the two terminals and listen for a click.
If you do hear a click, you could consider the relay to be a go, and if you do not hear a click, you will have to replace it.
A not-so-foolproof method, so you should have your multimeter ready and proceed to the next test.
#3. Check for Resistance.
If you search for an electrical diagnostic book, this is how to properly test a relay. You simply set your multimeter to measure resistance and connect the correct terminals to complete the circuit.
You should read anywhere from 50 to 120 ohms of resistance for a properly functioning relay. If you have a relay that reads out of limits or has excessive resistance, you would then replace the relay.