If the turn signal is not working on your car, then this article may help.
Turn signals are an immensely important part of car signalization. Without them, you can cause confusion on the road or even cause a car accident.
So, knowing a thing or two on this topic may come in handy.
It’s worth mentioning that these reasons also apply, to some extent, to modern LED systems so all of this might be useful for them also.
You can also watch our video on this topic either here or on our YouTube channel.
TURN SIGNAL IS NOT WORKING-COMMON REASONS
1. BAD LIGHT BULB
A bad light bulb is the most common reason why the turn signal is not working.
Tell-tale signs you should check the bulb are:
- Only one turn signal doesn’t work but all the rest do.
- The dashboard warning light works faster on one side than the other.
- Accompanied by this, one side of the turn signals will blink faster (the ones that work).
To check this out, simply take out the bulb and see if the filament is OK and that it is not burnt out.
With LED bulbs it may be harder to conclude since there is no filament but they either work or not.
If you find that the bulb is OK, then best to check if there is an electrical input to the bulb (both plus and minus input).
The easiest way to do this is by checking the contact in the bulb socket with an electrical tester or multimeter.
Know that this is also a starting point for resolving the whole problem.
If the bulb is burnt out, the problem is solved. But if there’s no electric input to the bulb then start searching from there.
If you want to see how to use an electrical tester, click here to read our article written specifically on that topic.
When the turn signal is not working at all (nothing happens when you flip the stalk switch)check the fuses first.
Every car has a specific fuse for the turn signals. You can find where it’s located by looking into the user manual or the little maps found on the fuse box lids.
You can check the fuse visually (that the filament inside is not burnt out) or use a tester or multimeter.
For more information about how to replace a fuse, click here to read the article on that topic and watch the video.
3. BAD ELECTRIC CONTACT, LIGHT BULB SOCKET OR ELSE
One more reason the turn signal is not working is bad, filthy, or damaged electrical contacts.
The most common place for problems is the contacts on the bulb socket but also various connectors on the installation.
Check this out if there is no electric input to the bulb socket, if the fuse is OK, and especially if just one turn signal doesn’t work.
Tell-tale signs that this is the problem are rusty, filthy contacts or ones that have black charcoal-like marks on them.
The main hotspots for this problem are bulb sockets, contacts on the bulb, connector pins, and else.
When checking also make sure that all the connections are nice and tight.
Especially pay attention to connections that may be in damp or moist places.
4. BROKEN WIRES
If the contacts are OK, broken wires may be a problem.
It is a rare reason but worth checking if everything else is OK but there is still no electric input to the socket.
Especially pay attention to this if there were some recent repairs in that part of the car or if there was some kind of physical damage or impact.
Also, check places on the wiring installation where the wires bend, like where they get out of the connector for instance, or where the wires go through a tight spot.
Older cars are especially prone to this problem as the wires get brittle over time.
5. BAD TURN SIGNAL RELAY
Some common signs of a bad turn signal relay are:
- The turn signals don’t work at all.
- They work unevenly instead of at a normal pace,
- The dashboard warning light is on all the time,
- You may hear a buzzing sound instead of the usual clicking,
The relay looks like a small black box.
It is usually located near the fuses or in the fuse box but you should search the user manual or the internet to find it easily.
Replacing it is simple, just pull the old one out and plug in the new one in.
To avoid losing time and searching, know that in lots of modern cars, the relay may be integrated into the hazard light switch.
Besides this, the relay might even be non-existent as the turn signals are controlled by the ECU.
So, once more, to save time, make an inquiry to where it is located and does the car even have a relay at all.
6. BAD STALK SWITCH
The last reason on our list for why the turn signal is not working is a bad stalk switch.
That is the switch behind the steering wheel.
Some usual signs that this might be a problem are:
- A crunching sound and feel when you press or lift the switch lever
- The lever is tough or impossible to engage.
- It will not stay in place and disengage when the steering wheel turns.
These switches are very durable on most cars and rarely cause problems. Problems appear mostly due to some kind of physical damage (like hitting the switch lever for instance) or material fatigue.
Material fatigue is common, especially on older or high-mileage cars.
One more tell-tale sign that the stalk switch is the problem is that you may not be able to use the high beam lights or turn on the wipers for instance.
This is because, on most cars, the stalk switches have multiple functions and combined mechanisms so if one function doesn’t work it may affect the other.
So, for the end a summary:
- When only one turn signal doesn’t work start solving the problem with checking the bulb.
- If the bulb is OK, check the electrical input to the bulb socket.
- No input to just that one socket (but the other sockets are OK) means checking for bad or filthy contacts, broken wires, or bad connectors.
- When the turn signals don’t work at all, check the fuse first.
- Check the relay if only one side of the turn signals works, if you hear a buzzing sound, and if the dashboard light is on all the time.
- If the stalk switch is hard to push, if it crunches when pushing, it won’t stay in place, consider the stalk switches as a possible problem.
One more thing, know that on modern cars with their complex electric and electronic systems, the turn signals may be intertwined with other systems. Because of this, problems may be caused by something else than what we’ve stated here.
In the end, as soon as you notice a turn signal problem, solve it as soon as possible as it is a huge matter of safety, both for you and other participants in traffic.
Written by: Sibin Spasojevic
Former car technician, life-long car and DIY enthusiast, author for Despairrepair.com