Short in taillights

My taillights bulbs keep shorting out.
Experienced mechanics share their insights in answering this question :
When dealing with an exterior bulb that continues to burn out, the first plan of action would be to have a qualified technician perform an electrical diagnostic for your taillights. This should reveal whether the proper amount of power and ground is on the circuit. Also, check for corrosion in the wiring or in the connector. There could also be some kind of short to the power causing the bulb to burn out time and time again.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

There are several reasons why your tail lights aren`t working, including a bad light bulb, damaged fuse, and corroded light socket. While you could try to solve the problem yourself, it`s better to leave it to professional mechanics like RepairSmith.
Bad Switch: One common reason for the Parking Brake light to stay on is a failing or failed switch. This can be checked easily by jiggling the handle after it is down. If the light turns off (or turns off and then back on), the switch is the most likely culprit and will need to be replaced.
A tail light in a shape of a LED bar with four E-approved functions – reversing light, indicator, brake light, and red position light approved as a tail light.
Fuses for everything electrical, including your tail lights, are always found in the fuse box. They are usually located under the hood or in the cabin. Fortunately, you can fix this type of problem by replacing the fuse.
Your rear lights are controlled through the same switch that controls the headlights. Power is channeled through a relay to the rear lights, illuminating them when the switch is engaged.
The most common cause your brake lights stay on is because of a faulty brake light switch or sensor. It can also be caused by a faulty brake pedal or a malfunction in the electrical system. If you recently replaced the rear light bulbs when it occurred, you may have installed the wrong light bulbs.
Tail lights are red lights on the back of a vehicle. They are turned on whenever the head lights are on.
There are actually a number of reasons why your tail lights could not be working but your brake lights are, including: Bad tail light fuse. Bad tail light bulbs. Socket failure.
Check the fuse.

A blown fuse usually causes both lights to go out. On newer cars, the tail lamps can be fused separately and/or each bulb or shared circuit can be fused. A fuse can be blown due to other problems, so you`ll need to check more than just the fuse, but it`s the right place to start.

LED tail lights have a high failure rate. Fortunately, they`re easy to repair or replace as a do-it-yourself job. Although LED tail lights are designed to last, moisture may enter worn housings and could corrode circuit boards, causing the resistors to fail.
The stop lamp fuse is in the left kick panel inside the vehicle. It is a 15amp fuse that powers the stop light switch on the brake pedal.
How long do tail lights last? Some tail light bulbs, such as incandescent ones, can last for up to five or six years. However, the average life expectancy of LED bulbs is 12 years.
Bad Socket. If you have a single brake light out and the bulb is good, then the next step is to check the light socket itself. Brake light problems can include a socket whose connections are dirty or corroded or one whose wiring has become worn to the point where it`s only making an intermittent connection.
Tail light relays are a vital part of any car on the road. Relays take out a manual aspect, or possibility for human error, in an electrical process. Tail light relays are linked to the headlight system of your car.
The brake light switch sensor lets the ABS module in your car know when you`ve applied the brakes and indicates that it`s time to start the ABS hydraulic pump. That`s why if your ABS warning light comes on, there`s a chance that your faulty brake light switch is the culprit.
Tip: When your brake lights stay on while your car is stopped, it can drain your battery. It`s important to resolve brake light issues right away so as to not drain your battery.
If you have a malfunctioning tail light, it could be a matter of a blown fuse. The fuses work with your car`s electrical panel and if they`re blown, it can cause several lights to stop working. Replace the fuse and see if this helps. Another issue may be related to your wiring.
Pull up on the brake pedal and if the lights go out, switch mis-alignment or pedal position error is the likely cause. The final possibility is a wire shorted to power. Unplug the brake-light switch and if the lights stay on, a short circuit is the case. Finding such a shorted-circuit, is best left to a professional.
The main difference between tail lights and brake lights is that the former lights up as soon as the headlights are turned on, while the latter only engages upon stepping on the brake pedal. While both lights are red, brake lights tend to emit a more luminous red light.
There are 3 choices for the type of light: halogen, HID, or LED.
Tail Lights are mounted to the rear of the car above the bumper. They are red in color and have accompanying white lights beside them to indicate when the vehicle is in reverse. When you`re on the road, tail lights make other car`s aware of your presence so that you can travel safely in the dark.
Brake tail lights are the lights on the back of the car that turn on when you press the brake pedal. This is important for safe driving conditions because it provides specific notice to other drivers behind you when your speed is likely to change.
The automatic lights you are referring to are likely the Daytime Running Lamps (DRLs). These are an automatic safety feature that is more for other drivers around you than for your driving comforts. This system does not turn on the tail lights, and they are dimmer than your normal headlights.
Why does my trailer lights have 3 wires? one for the tail light function, one for the brake light function, the third typically white is the ground used to complete those circuits. The turn signal is accomplished by supplying power to the brake light circuit and then interrupting it periodically.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Alternator dead short when power applied.
ANSWER : Firstly, with the battery disconnected you will have continuity between the positive cable to the ground of the body or engine if you have any components hooked up or have fuses in. You are getting a complete circuit through some of these components. You will need to check to make sure all of the wiring on your power side is not touching ground before going through the components.

Disconnect the big main cable to the alternator and see if the short goes away. If it does, then use your meter to measure the ohms between the alternator post and the alternator case. You should have continuity in one direction and if you switch leads you’ll have no continuity. This will tell you the diodes are good or shorted in the alternator. If you have continuity in both directions then the large post is grounded or the internal diodes are bad.

If you can’t get it to work and you decide to get this fixed, consider contacting a certified mechanic who can diagnose your electrical issues firsthand and fix it accordingly.

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battery cable is too short to reach battery connection. Had to replace the connection because it broke off and now cable to short
ANSWER : You can purchase battery terminal ends with cables attached at most automotive part stores. You want to find the same gauge/thickness of wire or slightly larger.

Then you’ll need a lug or crimp fitting that matches the size of the cables to attach them together and a pair of heavy duty crimping pliers.

Another alternative is going to the dealer and trying to find a new harness.

If you feel like you need assistance with this, feel free to contact a certified mechanic who can help you with any of your battery needs.

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When I am braking the headlights and taillights blink.
ANSWER : Hi there. There could be a short in the brake light switch causing the lights to flicker. Check the circuits in the brake light circuit to find a short to ground. Look for any wires that are fused to other wires. Repair any wires that are burned into other wires. If you need further assistance with troubleshooting your flashing lights, then seek out a professional, such as one from Your Mechanic, to help you.

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New cv axle too short
ANSWER : It appears that the 94-6007 is the correct part number. I’m assuming that this is for the left side, as the axle for the right side is over 10 inches shorter. I would suggest that you measure the compressed length of the shaft assembly. According to the specifications, it should be 35 5/8" long, when compressed. I have run into problems with some aftermarket parts having manufacturing discrepancies, and the specs will be off slightly. If the measurement of the axle is correct, you may want to check for other issues. Are the transmission mounts collapsed/shifted and causing a problem, control arm mount bushings perished, or something else that will have the engine/transmission sitting off to one side and causing a problem? If you feel you could use a hand in identifying/repairing the problem, contact a certified mechanic, like the mobile mechanics at

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Searching for a short, I found something I don’t quite understand 2001 Chrysler 300M
ANSWER : Hi there. If the vehicles electrical system has been altered with the addition of an aftermarket radio or anything else has been changed then it is hard to diagnose. I would need to see the colors of the wires to know where they go. If you know that the wires you are testing are a power supply wire then they should have no resistance in them. Keep in mind to properly test them they need to be isolated from the system which means that they need to be disconnected at both ends. If you do not do this then your readings will be incorrect.

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Taillights and dash lights not coming on
ANSWER : A short is a possible cause. Was the fuse you replaced blown? Did the new one blow as well? Shorts can be tricky to track down, especially if they are intermittent. Check your taillight/turn bulbs, and your front marker/turn bulbs closely. The filament could be broken inside, shorting to another circuit or ground. I recommend having a certified technician, such as one from YourMechanic, come out to your car’s location to run a diagnostic inspection of your inoperative lights, and suggest the best path to repair.

Read Full Q/A … : Short in taillights

Short in taillights
ANSWER : When dealing with an exterior bulb that continues to burn out, the first plan of action would be to have a qualified technician perform an electrical diagnostic for your taillights. This should reveal whether the proper amount of power and ground is on the circuit. Also, check for corrosion in the wiring or in the connector. There could also be some kind of short to the power causing the bulb to burn out time and time again.

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Replace plastic cover over right taillight unit
ANSWER : Unless Cadillac offers the lens as a separate and replaceable separately component, there is no way to repair the lens by itself. The only "repair" is a red film/tape that is available at your local auto parts store. It will not look the same as the original piece and note that in some states/localities, it not considered an acceptable repair. It may be against local vehicle inspection codes, leaving you open to traffic tickets. Unfortunately, the only proper repair is most likely a complete tail lamp assembly replacement.

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