As the tail light is very important when driving, the laws in almost any country do not allow you to drive without a working tail light. So it is important to keep the tail light checked and working before start driving.
But I see a lot of people reporting that their tail light fuse keeps blowing for no reason. What could be the reason for that, and how can you fix it? That is what I’m going to discuss in this article. So stick around until the end to find out what you’ve been looking for.
Table of Contents
- Why do my tail lights fuse keep blowing?
- Why do my headlights keep blowing the fuse?
- Can you drive with a blown fuse?
Why do my tail lights fuse keep blowing?
The simplest explanation is that the bulbs (brake light bulbs) on the circuit have corroded and the contacts have melted, resulting in a short. Another type of bulb fault occurs when the filaments in a dual filament bulb short together.
Also, your wiring or one of the brake light circuit’s bulbs likely has a dead short somewhere in the car’s frame, which serves as ground. Keep in mind any additional trailer harnesses.
Where a heavy object has pressed against the wire, pinched it, and gradually worn through with vibration over time is a likely cause. Although it is possible and the simplest thing to check by pulling all the brake lights, a bulb short is less likely to have occurred.
A short circuit in the wiring:
This can happen if the wires leading to the tail lights are damaged or frayed, causing them to come into contact and create a direct path for electricity to flow.
Fixing a short circuit
If the problem is determined to be a short circuit in the wiring, the mechanic must locate the exact location of the short. This could entail following the wiring from the fuse box to the tail lights and inspecting the wires for damage or fraying.
After locating the short circuit, repair or replace the damaged wires. If the issue is limited to a small section of wire, they may be able to repair it by splicing in a new section. If the wire is severely damaged, the entire wire harness may need to be replaced.
The cost of repairing a short circuit in the wiring will vary depending on the nature of the problem and the cost of replacement parts. However, it usually ranges between $50 and $200. In some cases, the cost may be higher due to the complexity of the repair and the cost of the parts.
A problem with the tail lights themselves:
A faulty tail light bulb or assembly can cause a large amount of current to flow, causing the fuse to blow.
If the issue is determined to be a faulty tail light bulb or assembly, you must inspect the tail lights to determine the specific problem. Checking the bulbs to see if they are burned out or loose, as well as inspecting the wiring and connections to see if they are corroded or loose, may be required.
You will need to replace the faulty bulb or assembly to resolve the issue. Depending on the make and model of the vehicle, this could be as simple as replacing a bulb or as complicated as replacing the entire tail light assembly.
The cost of replacing a tail light bulb is typically between $10 and $20 per bulb, but this can vary depending on the vehicle’s make and model. Replacing a tail light assembly can be more costly, ranging from $50 to $200.
A problem with the electrical system:
A problem with the vehicle’s electrical system, such as a faulty alternator or battery, can increase the amount of current flowing through the system, causing the fuse to blow.
If the problem is determined to be a problem with the vehicle’s electrical system, such as a faulty alternator or battery, you will need to run a series of tests to pinpoint the exact problem. This may entail using a diagnostic tool to look for any stored codes, running a charging system test, and inspecting the battery and alternator.
To resolve the issue, you must replace the faulty component. If the alternator is faulty, it must be removed and replaced with a new one. If the battery is the source of the problem, it must be removed and replaced.
The cost of replacing an alternator varies greatly depending on the make and model of the vehicle, but it usually ranges between $200 and $600. A battery replacement usually costs between $50 and $100.
The light can’t accommodate the bulb’s size.
To our surprise, the severity of this common problem exceeds our expectations. By connecting the meter, you can verify that it is your case (at which the short finders are situated). The accurate reading should range between 5 and 10 Amps.
Problems have developed if the number surges by 10 Amps or even more. The main offenders, in this case, might be internal damage or incorrect wattage.
Failure of the fuse terminal.
Poorly connected fuse terminals have the potential to blow and heat the fuse. Check to see if the fuse needs longer times to ignite (even 2 or 3 extra seconds matter). If so, there are overheating problems. The system is more than capable of being destroyed by a combination of an environment that is too hot for the fuses and their own excessive heating.
It’s also not difficult to spot signs of terminals with poor contact or blown fuses. Even beginners can clearly see the signs of rapid melting all around the fuse.
Why do my headlights keep blowing the fuse?
If the fuse takes a while to blow (more than a few seconds) and the current drawn by the bulb is reasonable, overheating is the most likely cause. Fuse terminals that are not making good contact may also contribute to the fuse heating up and blowing.
You might have a high-resistance short
Although you might have a high resistance short, which you don’t because of the light functions, you can check for it by unplugging the bulb and measuring the resistance between the fuse terminal and ground; it should be infinite. The bulb might not be as bright as the one on the other side, which is another indication of a high resistance short.
You can check if the light bulb is too big by connecting your meter to the location where the short-circuit detector was; you should see about 5 Amps. Check the bulb; it might be the wrong wattage or have internal damage that behaves like a high resistance short if the draw is up around 10 Amps.
If the fuse takes a while to blow (more than a few seconds) and the current drawn by the bulb is reasonable, overheating is the most likely cause. Fuse terminals that are not making good contact may also contribute to the fuse heating up and blowing. You may notice melting around or on the fuse if the fuse block terminals are not making good contact.
A hot environment near the fuse, coupled with the heating caused by the current drawn by the headlight, may be sufficient to cause the fuse to blow.
Does one fuse control both headlights?
The vehicle’s make and model will determine this. Some cars have fuses for each headlight individually, while others have a single fuse for both headlights. In some circumstances, a relay rather than a fuse may be used to protect the headlight circuit.
To learn how the headlight circuit is safeguarded in a specific vehicle, it is crucial to consult the owner’s manual or a qualified mechanic. To prevent further damage to the vehicle and to ensure the safety of the driver and passengers, it is critical to have any fuse that keeps blowing fixed as soon as possible.
Can you drive with a blown fuse?
Depending on which fuse blew, Driving without functioning headlights, especially at night, would be risky if the fuse that controls the headlights had blown. It is dangerous to drive without airbags, turn signals, or other safety features that the fuse may control, so the car should be taken to a mechanic as soon as possible.
Although it is technically possible to drive with a blown fuse for that feature, if the blown fuse controls a non-essential feature like power windows or the radio, it is still advised to fix it as soon as possible.
It’s crucial to remember that if a fuse keeps blowing, there may be an underlying problem, and it must be fixed as soon as possible to prevent further harm to the car and to ensure the driver’s and passengers’ safety.