Turn Signals Don’t Work When Headlights are ON – Diagnosis and Fixes!

Modern cars are equipped with turn signals. Every car driver understands the necessity of the turn light not just from safety aspects but also from legal point of view. Whenever you have tried to make a turn, the car turn signal makes a beeping noise. But what if you don’t hear this sound? Your turn signals don’t work when headlights are ON is an indicator that your car turn signal has problems. Failure to use turn signals results in numerous accidents every year.

For the safety of both you and other drivers, you should fix a broken turn signal as soon as possible.

In the following blog, we will dive into the details of the reasons of turn signal won’t blink with headlights ON condition.

Reasons Turn Signals Don’t Work When Headlights Are ON

If your turn signals don’t work when headlights are ON, you can take it to the mechanic. But you can save dollars if you diagnose it yourself. However, for that, you have to be aware of the possible causes of the turn signal not flashing. Here are a few reasons for your blinker lights not working.

Blown Fuse

A blown-out fuse is one of the main reasons for your turn signal not flashing properly. The modern car consists of multiple wiring harnesses connected to the engine control unit. The wiring harness relay signals to the ECU upon the driver’s indications. However, there are fuses to control the supply of power beyond the threshold limit. So, due to the excess power fuse controlling the power supply, blinker lights could have blown out. Thus, it won’t make your led turn signals operate efficiently.

Malfunctioned Turn Signal Switch

Stalk or Switch is an essential component of your car. It conveys signals to the blinker light indicating which direction the driver has intentions to turn. So, if your turn signal won’t blink with headlights ON, the possibility could be that the switch is unable to transmit the signal.

Oxidation of Bulb Socket

Due to UV rays, the bulb oxidizes and produces gases that affect the functionality of the turn signal bulb. Turn signals don’t work when headlights are ON, it could be due to water seeping into them, causing rust. Rusting of the parts reduces the connection integrity between bulbs and sockets.

Fused Light Bulbs

Another top reason for the car turns signal not blinking is that the life of the bulb has been exhausted. With the passage of time and high use, the bulbs lose their efficiency and thus become dead.

Broken Flasher Module

The turn signal system receives power from the battery through the flasher module. Power cannot enter the turn signal once it breaks. Since there are numerous systems that are in connection to the turn signal system that could malfunction simultaneously. A lead piece connects the flasher module to the fuse. It won’t function if this is broken or damaged. You will have to buy specific turn signals along with best aftermarket headlights for efficient functioning.

Turn Signal Won’t Blink with Headlights ON – How to Fix?

Car turn signals are not difficult to fix. You can save money if you diagnose it well and understand the issue. From the above, you may have got a picture of what could be the possible reasons for the failure of car turn signals. So, here are a few ways to narrow down the cause and resolve it.

One Side Turn Signal isn’t Responding

There is a possibility that only one turn signal will function and the other won’t. The chances are your led turn signals bulb is dead. If it is the case, replacing the burned-out bulb should be a straightforward process. Make cautious to inspect the socket for rust if you plan to repair it yourself.

Both Turn Signals are not Working

If neither of the turn light is operating, there is probably a blown a fuse or a broken flasher to blame. The turn signal won’t blink with headlights ON. Then it might also result from rusted sockets or dead bulbs, which are a little trickier problem. You should go through the car manual before fixing it. However, it is the best practice to visit the mechanic for it.

Turn Signal not Flashing

The turn signal flasher or turn signal switch may malfunction if the lights are in good condition but not flashing. To resolve the problem of the turn signal not blinking with headlights ON, you have to gain access to the signal switch electrical connector and replace it. Also, there can be corrosion on the wiring that may be interrupting the signals. Remove the rust and rewire the components.

Too Fast or Too Slow Blinking Turn Signal

A bulb on the side is probably out if your turn signal is blinking more quickly than usual. Turn signals abruptly stop the circuit that flashes the front and rear lights. Excessive damage can cause front and rear turn signal lamps out. Turn signals don’t work when headlights are ON or not functioning properly because the resistance regulating time could malfunction.

Turn Signal Light Continuously ON

Other vehicles on the road may get confused if your turn lights don’t go OFF. Depending on the severity of the issue and the type of vehicle you drive, you can typically fix this problem.

The problem could be with the switch or flasher module. You can resolve it by changing them.

Frequently Asked Questions