What causes rear light failure warning light?

A rear light failure error indicator in the car’s dashboard is often caused by several different problems, including four of the most common ones listed below.

  • Problems with the Sensor
  • Electrical Issues
  • The rear light bulb is bad or Loose
  • Level of humidity around the bulb

Therefore, if you want to get to the actual source of these issues, you may need to troubleshoot each to determine why this warning light is turned on.

Problems with the Sensor

It is important to note that there are sensors strategically positioned all around your vehicle. For example, there are gas sensors, engine sensors, hydraulic sensors, and tail lighting sensors that provide specific information about your vehicle and its operation.

Therefore, if the sensor detects a failure or malfunction in the rear lighting, the rear failure warning light will appear on your dashboard to alert you.

Electricity Issues

Another common cause for a rear light failure warning light is an electrical issue. For instance, if the wiring is faulty or a fuse is bad, this rear light failure warning light will appear on your dashboard.

The rear light bulb is bad

According to information published on cartipsdaily.com, the average life expectancy for rear light bulbs is about 5 to 6 years. So, it is quite common for a rear light bulb to go bad at any point in time.

When this happens, the rear light failure warning light will start flashing to notify you.

Level of humidity around the bulb

Even though humidity is not supposed to get underneath the housing components that surround the rear brake lights, it does happen.

Fortunately, if the sensors are working properly, these are problems that can be detected in advance. For instance, once these warning lights come on, it gives the driver a chance to take the appropriate measures (i.e. wipe the condensation away, install new plastic housings, etc.).

How to fix a rear light failure warning light?

Just like the cause can differ from situation to situation, the fix can vary as well. Therefore, if you want to ensure the rear warning light is turned off and corrected completely, you may need a mechanic to assist you with identifying the exact cause of the problem first.

For instance, if the sensor or the light bulb is bad, the mechanic can fix these problems by replacing each of them with new ones. Or, if there is an issue with faulty wiring, the wiring may need to be reinstalled before the warning light will turn off.

How much does it cost to fix a sensor on a car?

Once the problem and solution have been identified in each situation, you will need to know the cost of these repairs. And, here is what you can expect to pay.

Cost to Repair problems with the Sensor

The average cost of most sensors can range between $20 to $100. The typical labor charges may vary significantly based on the auto shop and other factors. For instance, some repair shops may charge approximately $150 in labor to replace this sensor.

Cost to repair an electrical shortage

If the wiring is damaged, in a rear-end light, the auto technician may charge around $70 to 120 an hour for these services.

The cost to replace the bad rear light bulb

If the tail light is broken or damaged, you will most likely change out the bad rear-end light bulb yourself. Therefore, the price, without the labor, can range between $4 to $6 for a LED tail light bulb.

Cost to Repair Level of humidity around the bulb

The fix for this type of problem, it may cost you little to nothing. For instance, all you need to do is to remove the housing and wipe up or dry the condensation.

Can I drive with a broken rear indicator?

The answer to this question usually varies based on the cause. For instance, if the sensor needs to be replaced, you may be able to drive the car short distances until the sensor is replaced.

On the other hand, if the rear-end light is broken, it needs to be replaced immediately before driving. And here is why.

  • Unsafe to drive without working lights
  • It is illegal, every car is required to have 2 tail lights in good working condition


There are many different reasons why a rear failure warning light will appear on your dashboard. Four of the most common include problems with the sensor, electrical issues, bad rear-end light bulbs, or high levels of humidity inside the housing.

Additionally, each of these repairs should be performed as quickly as possible before placing the vehicle safely back on the road.

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