Turn Signal Problems And Ways To Fix Them

Figuring out what is causing turn signal problems can be a daunting task, especially when it’s a modern car with a hoard of electrical connections. You actually need time and some insight to decipher what the problem is. There could be problems in different parts of the signals like bulbs, flasher units, wires, connectors, fuses,… Nevertheless, it is not always necessary to head to a mechanic at the very first instance, and turn signal problems are not among the problems you shouldn’t fix yourself.

8 Turn Signal Problems

Issues with the blinkers not working are not restricted to the five we are discussing here. However, these five are the most commonly faced by car owners. In fact, you can find these issues in vehicles of all sizes – hatchbacks, sedans, trucks, SUVs, minibusses, and more. So, let’s discuss this one by one and see how to fix blinkers on your car.

turn signal troubleshooting
Turn signal troubleshooting (Photo: Getty Images)

1. Either turn signal isn’t working

It is one of the most common turn signal problems in vehicles and the fix for it is quite simple. Check the bulb – through the engine bay if front; through the boot if it’s rear. You can also do it by removing the lens. Make sure that the two filaments of the bulb are connected and that the glass is not dark already. In either case, simply replace the bulb. Also make sure that the socket is in fine condition, in case there is corrosion, you will need to replace it.

2. My hazard lights fail to work but the turn signals do

Odds are that the hazard lights are in the same circuit as the turn signal lights. So, the case could be one of these:

  • A faulty hazard light flasher
  • If the flasher is fine, it could be the fuse
  • A bad connection at the turn signal switch
  • A loose connection in the circuit that connects the turn signal switch and the flasher
  • An electrical open circuit/ short circuit in external lights wiring

If the reasons are either of the first two, you will need to change the flasher or the fuse, in the rest of the cases, you just need to set the connection right.

3. Turn signal lights don’t work

There can also be a situation when neither of your signal lights is working. In most cases, it is a blown fuse or a defunct flasher. In other cases, it could also be a faulty signal switch. You can fix these easily using your car’s repair manual.

turn signal problem
Easy steps to fix wrong turn signal (Photo: Onaspark/Youtube)

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Apart from these, there could also be other problems like damaged bulbs or corroded bulb sockets. If you can, check the ground connection of the bulb. If you can’t, make sure you get it checked by a mechanic. Besides, it could also be an open or short circuit which is easy to fix yourself.

4. Turn signals don’t flash

If the turn signal lights and emergency lights have stable lights, you should check for a burned-out bulb first. If not, test the turn signal flasher and check the turn signal switch. In the first step, you need to identify wires and the best way to access the signal switch electrical connector. Besides, make sure that you disable the system to prevent airbags from inflating if your car has them. In fact, the manual has detailed guidelines for each particular model.

5. Turn light don’t turn off

The reasons for this failure might be either the canceling finger inside the switch is broken or the canceling cam/clockspring is broken. For the former problem, you need to replace the switch and for the second one, you need to replace the cam or assembly, depending on your specific model.

In the majority of cases, solving this problem isn’t too difficult. Besides, the car owner should consult the repair manual for the particular car make and model. Other than that, if your model has airbags, you will need to disable the system for safety reasons as the symptom above.

6. Turn lights flash too fast or slow

Changes in the flashing rate of the turn signal lights aren’t common and hard to notice as one of turn signal problems. In case this occurred after replacing the flasher or one of the light bulbs, you must have installed the wrong type of flasher or bulb for your vehicle model. Or else one of your light bulbs must have burned out. A burned-out bulb may cause the indicator light to flash faster.

There are other problems that can lead to a slower or faster change in the flashing rate:

  • A loosely connected turn signal switch.
  • Poor power connection or grounding at the lamps.
  • If they are flashing faster than normal, the alternator may be overcharging the battery.
  • If they are flashing slower than normal, the alternator may be undercharging, or your battery may be undercharged.

7. Dashboard’s turn indicators don’t flash

You may know there must be something wrong with your turn signal lights as the indicator lights on the instrument panel illuminate but don’t flash as usual.

  1. Firstly, check if your turn lights work properly. If they come on but don’t flash,  the flasher unit is most likely bad.
  2. If one of your signal lights doesn’t come on, then you check the bulb; check the bulb socket for damage or corrosion; check for poor ground at the socket.
  3. Check for an opening in the circuit, between the light(s) that doesn’t work and the turn signal switch.

8. Turn indicators don’t work but turn signals do

Direction Indicators
Turn indicators in the dash cannot work like they should (Photo: yourmechanic.com)

One problem of turn signal problems you may encounter is that your indicator lights don’t work, but outside the turn lights work just fine. Possible causes can be:

  • a bad ground
  • a problem with the flasher unit
  • blown out indicator bulbs
  • corroded bulb sockets

If necessary, take a look at your vehicle repair manual to gain access to the bulbs on the ground connection and instrument panel.

Although some models use a separate light for the right and left turn indicators, others use a single light for both turns.

  • If your instrument panel has only one indicator light for both right and left, check the flasher unit. Some vehicle models combine the taillight, brake light, and turn signal into one light bulb.
  • If you replaced one of the lamps, make sure the bulb is properly installed.
  • If the two separate instrument panel indicator lights don’t work but the outside turn signal lamps work, check the indicator light bulbs and flasher unit.

How To Fix Turn Signal Problem

signal lights not working
Why signal lights are not working? (Photo: James Ruppert)

So how to fix turn signal? To start with, you need to park the vehicle on level ground with the engine “OFF”.

Step 1

Make sure not to start the engine while turning the ignition key to the “ON” position. The electrical system will be powered up for testing.

Step 2

Locate the fuse panel or the power distribution center (PDC) to check all system fuses. You need to pay attention to locate exactly where the fuse is.

Step 3

When a turn signal flasher or replay fails the blinkers will not operate or come “ON”, but not blink. The purpose of the direction signal system is to operate with a flasher or blinker unit that interrupts the signal which causes the blinking action.

Step 4

When a turn signal switch is false, the system will short or go “open” leading the blinker not to operate. Then, you use the test light to test the input and output power circuits.

Step 5

In case the module has a problem various lights will not operate and it needs to be updated or reprogrammed, a lighting module is used for controlling purposes.

Knowing more how to quickly fix the turn signal problem:

Summing Up

These are the problems and easy step-by-step guidelines on turn signal troubleshooting. If you have been regular with the service schedule and follow the maintenance tips for your car, these turn signal problems will not be recurrent.