Driving just 4 blocks to get to the grocery store? You still need functional turn signals. Not only is their usage required by the law, but it’s the sole way to let others on the road know you’re turning the car.
In many cases, the turn signal works sometimes only. The driver will know about this because either they will not hear the clicking sound, or they won’t see the little light on their dashboard. Occasionally, it is completely broken. This can be super frustrating. Imagine needing to go somewhere urgently and your car won’t give you the green signal for it!
Turn Signal Works Sometimes: What Could You Do?
A malfunctioning turn signal puts a lot of lives in danger. You could cause serious injuries to others and yourself, not to mention the damage to your precious car. That’s why you must make sure your turn signals are operational at all times.
Before you consider bringing your car to the mechanic and paying hundreds of dollars for a fix, check if you can diagnose the issue and repair it yourself. If there are no ways for you to handle it by yourself, bring it to a professional immediately.
What many people fail to realize is that the turn signal system connects to multiple systems in the car. For instance, the turn signals and the brake lights, parking lights, and warning lights are connected by the same system. Any problem in any of these components could reflect on the rest of the systems.
And why we ask you to give diagnosis a try is because the matter might take only $10 to fix. Why should you give someone $200 for it?
Today, we have rounded up the most common issues making turn signal work sometimes. We’ll also mention a solution for those.
In case you’ve already completed the search for the issue and have detected it successfully, you can jump right into the specific segment from here.
Why My Turn Signal Works Sometimes? Detecting 5 Reasons
The problem summary is that turn signals works sometimes – it flashes in only one side or one position or doesn’t flash at all. There can be five main reasons behind this:
1. Dead Light Bulbs
Ideally, turn signal light bulbs must last you about a few years. They will die eventually but some people are lucky enough to have their original turn signal lights last till the end of the car’s life. It is primarily determined by how much you drive – how much you use the signals in the process.
As these bulbs are rather inexpensive, it’s a wise decision to replace them and check if that solves the issue. If not, you have to dig deeper as this means the problem could be more complex.
2. Oxidized Bulb Socket
Don’t panic. At some point, every part of your car will experience some level of oxidation – a fancier term for rust. Things like dust and rust can stop your turn signal from working properly. It disturbs the link between the socket and the bulb.
Perform routine maintenance and cleanups to keep your car running smoothly. If the problem persists, waste no time in taking the car to a local mechanic.
3. Malfunctioning Turn Signal Switch or Stalk
Near your steering wheel, there should be a device that lets you turn the signals on and off. That’s the turn signal switch (stalk). If it fails to send a signal to the computer to let it know to turn the light on, it won’t work.
The issue could be with the switch or the wiring. If the switch keeps getting stuck, that problem is fixable. Anything more than that and you will need the assistance of a professional.
4. Blown Out Fuse
Almost everyone has heard the words “blown fuse.” Generally, this happens in households and offices. A fuse will break if you have plugged in too many things into the electrical outlets.
Or, the air conditioner is functioning on overdrive and the fuse blows. Simply flip the main breaker or reset the fuse and that’s done. However, in the case of a car, it’s not that easy.
Chances are, your fuse blew because there were too many signals lit at the same time. Or, the energy level got too high, melting the fuse. Blown fuses need to be replaced immediately. The good news is that you won’t have to spend an arm and a leg on a new fuse. Installation isn’t that hard either.
5. Ruptured Flasher Module
Your turn signal system has this thing called a flasher module. It transmits the power from the battery to the turn signal system. Once it breaks, power cannot move into the turn signal. We mentioned earlier that the turn signal system is linked to many other systems that may blow up at the same time.
The flasher module is connected to the fuse with a lead piece. If this is damaged or broken, it won’t work. You can’t DIY a fix for this one. Just take it to the local mechanic.
Check out this video tutorial on diagnosing common turn signal issues in your car. Also, you can check out this article to fix turn signal issues.
Troubleshooting Individual Problems
Now that the reasons are out of the way, let’s solve the issues by scenario.
One Turn Signal Doesn’t Work
Only one turn signal works sometimes? This is one of the most common issues this system can cause. To troubleshoot the problem, follow these steps:
- Check the bulb. Get through the engine compartment, trunk, or remove the lens to gain access to it. Depending on your car’s model, the access could differ. If needed, have a look at your car’s repair manual.
- The turn signal bulb is most likely going to be a two-filament type. Check to see if both filaments are in a good state or not, and whether or not the glass of the bulb has darkened. If any of the filaments look questionable in quality and the glass has darkened, replace the bulb (must be of the same wattage).
- Inspect if there is damage or corrosion in the bulb socket.
- If needed, check the power connections and the socket ground.
One Side of Turn Signal Won’t Work
This one is the variation of the first problem. Either the right or the left side of the turn signal doesn’t work. The dash indicator lamps may shine brightly but this doesn’t turn the lights on.
You might be working with a bad wire, a bad flasher relay, bad bulbs, a faulty switch, or a faulty connector between the signal switch and the flasher unit.
- First, check to make sure the bulbs are in working condition. No damaged filaments or darkened zones.
- Ensure there is no damage, wear, or corrosion on the filaments.
- Make sure the ground and power connections are functional.
- Have a look at the flasher relay. Refer to the previous section “Raptured Flasher Module.”
- Use a digital multimeter or test light to check outgoing voltage between the faulty turn signal and turn signal switch.
- As a last resort, check continuity from the ends of the wires, starting from the flasher relay as well as the turn signal switch.
Turn Signal Works Sometimes but Hazard Lights Don’t
The emergency or hazard lights might share a circuit with the turn signal one.
- When the turn signal works sometimes but the hazard lights don’t go off, you are probably dealing with a broken hazard-lights flasher.
- But, if the flasher unit seems okay, check out the fuse.
- Also, look for a bad line at the open section of the circuit connecting the turn signal switch to the flasher unit.
- Inspect any possible signs of a short circuit or an electrical open in the wiring that links to the external lights.
Blinker Lights Flash Too Slow or Too Fast
When the flashing rate of your turn signal lights changes, it can be traced back to many possible errors.
If this happened after you replace one of the light bulbs or the flasher, you could have installed the incorrect kind of bulb or flasher for your vehicle model. One of the light bulbs might have burned, causing the indicator to light to blink faster.
There are some other potential underlying problems that we must note:
- Poor power or ground connection at the car’s lamps.
- A loose connection in the signal switch.
- If the blinker is going off too fast, the alternator could be overcharging the battery.
- If the blinker is going off too slow, it may be a case of undercharging.
Broken Turn Signal Lights
We have moved on from turn signal works sometimes to turn signal doesn’t work at all anymore. Why? Because any unattended issues in your turn signal switch will lead to further deterioration of the condition. What used to work partially will be ruined completely.
When something like this happens, you’re most likely to be dealing with a blown fuse, a faulty turn signal switch, or a bad flasher unit.
Alternately, these problems might lead to this situation too:
- Check the condition of the bulbs.
- Check for damage or corrosion – visual inspection of the light bulbs.
- Ensure the ground connection is working right.
Turn Signal Won’t Flash
If the turn signal lights and emergency lights illuminate without flashing, check for any burned-out bulbs. That is amongst the most common causes. If not, a faulty flasher unit or a bad turn signal switch could be the reasons.
If necessary, conduct the given circuit checks:
- Verify the circuit connections haven’t experienced corrosion or loosening. They may be unplugged too.
- For the end section of the circuit, inspect the terminals or the wiring harness.
- Is there a bad connection between the flasher and the turn signal switch? Or between the ignition switch and the flasher?
- Check the turn signal switch’s power side connection for an open or bad contact.
- Lastly, see if there is any short or open in the lamp’s circuit.
Dashboard Turn Indicators Don’t Work
Alongside the “My turn signal works sometimes!” you’ve come down with another issue. The turn indicators on the dashboard are malfunctioning too. Although they are illuminated, the indicator lights aren’t flashing like always.
- Check to see if the turn lights are working alright. If they turn on but don’t flash, a bad flasher unit might be behind this.
- If a signal light doesn’t turn on, check the bulb. The bulb might have damage or corrosion, or even a bad ground.
- Verify there is no open in the circuit amongst the turn signal switch and the malfunctioning light(s).
Turn Signal Works but Turn Indicators Don’t
So, the outside turn lights are working just fine but the indicator lights inside aren’t. These are the possible causes:
- A bad ground
- Corroded bulb sockets
- Blown indicator bulbs
- Faulty flasher unit
- Faulty dashboard PCB
Some models are equipped with individual lights for the left and right indicators while others only have a single light for both.
- Check the flasher unit if the instrumental panel features a single indicator light for both wings. A few vehicle models bundle the taillight, brake light, and turn signal into a light bulb.
- If you’ve recently replaced any of the lamps, ensure the bulb was fitted properly.
- If the outside turn signal lamp lights up but the two separate instrument indicator lights don’t, check the flasher unit and indicator light bulbs.
Turn Signal Doesn’t Turn Off
Detecting the issues in a faulty turn signal switch is quite straightforward. Generally, depending on your vehicle’s model, the hardest part is accessing the switch electrical connector.
For this test, you have to identify the best way to reach the signal switch electrical connector as well as the wires. If your car features airbags, it’s best you disable the system or it could inflate suddenly. If necessary, refer to the vehicle manual provided.
- Your vehicle came with a repair manual. Go through it to know how to find the wiring diagram associated with the turn signals.
- Identify which wires transmitting power to the switch from the flasher and the wires are taking power to the turn signal switch from the switch. Observe the color designation on these and, if needed, the terminal number printed on the electrical connector.
- Find the turn switch electrical connector. Depending on the model, you might have to take out a column cover or an under-dash panel.
- Search for the wires you distinguished in step 2.
- Turn on the ignition key but don’t start the engine.
- Detect the wire supplying power to the turn signal switch on the connector of the switch.
- Take the test light and connect it to a good ground below the dashboard – a bolt or metal bracket will do fine.
- Work the switch to turn on the left turn signal light.
- Inspect the wire supplying power to the switch and probe it; this should get the test light to flash. In case it doesn’t, there’s an issue with the flasher unit. Or, there is a short or an open between the battery power source and the switch.
- At the connector, there should be a wire that transmits power to the left turn signal light. Back probe it to get the test light to flash. If that doesn’t do the trick, the switch is faulty and needs to be replaced.
- Repeat step 10 with the wire connected to the right turn signal lights. However, if the test light illuminates this time, the switch has to be replaced.
- Repeat the test on the right turn signal lights this time. Operate the switch. This time, the test light must flash when you back probe the terminal delivering power to the right turn signal lights. If the left turn signal lights illuminate instead, the switch has to be replaced.
Why You Should Always Use the Manual to Troubleshoot Problems
It’s easier to describe the more common issues due to which your turn signal works sometimes. However, troubleshooting the system isn’t always easy. You might have to access specific sections of the turn signal system that are, to an extent, hidden.
Expect to remove the steering wheel, covers, or even disable the airbag. If you trigger any one of these, it could set you up for bigger problems. You must refer to your service manual at any point you’re stuck.
Many people aren’t comfortable doing these to their vehicle and that’s completely fine! You don’t have to be all brave and take a screwdriver to your car if you’re not confident. Bring to a local mechanic. They will either consult the manual provided with your car or, the Haynes Manual – the usual book used in these circumstances.
As every model and make is different, they have to be 100% sure they are familiar with the system. This better equips them to diagnose and repair the issues correctly and safely. In any situation where you fear you can end up damaging your car in the process of damaging it, there’s no need to risk it. You will have to cough up a few hundred bucks, but it’s money well spent.
If that isn’t motivation enough, just know that if you get a ticket or end up in an accident for those bad turn signals, you will have to pay much more to fix that.
How Much Does Fixing a Broken Turn Signal Cost?
While a broken turn signal doesn’t impact your car’s system directly, it’s hazardous and illegal. We can give you hundreds of reasons to fix the turn signal at the first sign of malfunction.
Let’s accept that drivers who don’t signal are dangerous and annoying. In addition, you can’t go through a state inspection without a functional blinker signal. A broken signal reduces the all-around value of your vehicle.
Made up your mind about replacing it immediately? Great! Now let’s talk money – how much does it actually take to fix the “turn signal works sometimes” issue.
The specific price greatly depends on the mechanic, vehicle, and multitude of the signal problem.
However, installation costs (for the mechanic) range between $70 to $100. The parts could cost an extra $200 to $300. In total, the replacement of a broken turn signal could set you back anywhere from $270 to $400.
We cannot stress the importance of using the right parts for every section of the car. Not just the turn signals, to avoid accidents, you have to take care of every part of the vehicle.
Make sure to use a replacement bulb matching the part number of the one being replaced. The wrong fit could mess up the rest of the system, causing much bigger damages you will definitely have to pay to fix.
Your owner’s manual should say the proper bulbs for each part of the vehicle.
An incorrect bulb can cause the turn signal to flash too fast or too slow. Manufacturers will often apply a layer of grease to keep water away from the bulb sockets. Don’t wipe or remove the grease from the sockets when switching out defective bulbs.
When your turn signal works sometimes, it can be a problematic situation. You could have left the house with a perfectly functional car from front to the back and the blinker lights simply stopped midway. Fortunately, diagnosing and troubleshooting these problems is relatively easy. As long as you have the right knowledge and your trusted car manual, you should be fine. And there’s always a mechanic to help.