When a warning light comes on in your Jeep Wrangler, it means your car is trying to tell you something. The best thing to do when a brake light goes on is to check a few things before driving off.By Bassem Girgis – November 12, 2015

This article applies to the Jeep Wrangler JK (2007-Present).

The brake system is an important system, especially because it’s in charge of your safety. When a brake warning light turns on in your Jeep Wrangler, it means your car’s computer detected that something went wrong in your brake system. With the brake system being that important, it is recommended you don’t drive without checking some components to avoid the system failing. The brake warning light could mean one of a few things and this guide will help you in diagnosing the issue. Read on to understand why your brake warning light is on in your Jeep Wrangler’s instrumental panel.

Materials Needed

  • Flashlight
  • Jack and jack stands
  • Tire iron
  • Socket set

Step 1 – Check fluid level

It could be low.

The first and easiest thing to check when the brake warning light is on is the fluid level. Locate the brake fluid reservoir under your hood, right in front of the driver side, and check to see if it’s less than the max line. If it is low, top it off and inspect for brake fluid leak. Check the master cylinder and around it for any signs of wetness. Check under the vehicle for any brake fluid leak, especially the connections between the brake calipers and the brake lines.

Figure 1. Check fluid reservoir.

If the brake fluid level is proper, proceed to Step 2.

Step 2 – Check brake pads

It could be worn.

If the brake pads are too thin in your Jeep Wrangler, the brake warning light will go off. Raise your wrangler, remove the wheels, and remove the brake caliper. Check the brake pads’ thickness. If it’s less than 2-3mm, replace it. The longer you wait with the brake pads, the more damage you will cause, such as wearing the rotors out.

Figure 2. Thick vs thin brake pads.

If the brake pads are thick enough, move on to Step 3.

Step 3 – Check speed sensor

It could be faulty.

The speed sensor could go bad and cause the brake light or the ABS light to go on. The speed sensor is located behind the front wheels’ rotors. To get to it, you’ll have to raise the car and remove the wheels; you may have to remove the brake caliper and replace the sensor from behind the rotor. You can just unplug it by pulling it out.

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