Common Reasons Why the ESP BAS Light Comes On
There are a few different reasons why your vehicle’s ESP BAS light may come on. The reasons vary in likelihood and severity, but here we’ll go into detail on each possible reason.
#1 – Steering Angle Sensor Failure
One of the most common reasons why the ESP BAS light comes on is a faulty steering angle sensor. For the ESP part of the system to work, your vehicle needs to know how hard you turn the steering wheel when going around a corner.
If the measurements don’t match up with the readings from either wheel speed sensor, the system knows it needs to make an adjustment. However, if the system detects that the steering angle sensor is giving an incorrect reading, it won’t be able to figure out what’s going on and make the necessary adjustments.
Because the actual wheel rotation is done through a physical connection between the steering column and the steering rack (usually assisted by the vehicle’s power steering), the vehicle will continue to turn even if the steering angle sensor is faulty.
#2 – Wheel Speed Sensor Failure
This is another very common reason why your vehicle’s ESP BAS light comes on. Each wheel has a wheel speed sensor that tells the computer exactly how fast the wheels are turning.
These readings are compared to readings from the other wheel speed sensors to see if one of the wheels is spinning or losing traction. Keep in mind that if your vehicle’s wheel speed sensors are failing, you won’t have safety features like traction control or ABS.
#3 – Brake Switch Failure
Your car’s brake switch turns on the brake lights behind your car when you press the pedal, so other drivers know you’re slowing down and can react accordingly.
Sometimes (not very often) your brake light switch can fail, which can cause your ESP BUS light to come on. There are two reasons for this: First, it turns on to let you know there’s a problem. Otherwise, you might not even notice a bad brake switch.
Second, the brake switch often works in conjunction with brake assist to tell the computer that you’re trying to stop. If your car’s computer doesn’t know that you’re braking, it won’t know when to help in a hard-braking situation.
#4 – Wiring Issues
All of these different sensors communicate with each other and with the computer through cables, so if any of these cables aren’t sending accurate information, it will have a negative effect on your system.
The problem could be a complete break in a line that’s not providing the signal it needs. Or you could have too much resistance somewhere, or a short circuit, or crossed wires. Wiring issues are notoriously difficult to track down, but fortunately, they’re fairly rare.
Is it safe to drive with the ESP BAS light on?
The first thing you need to know when your vehicle’s ESP BAS light comes on is that you no longer have these advanced features available to you. Your vehicle will detect that the systems aren’t working properly and will disable both systems for your safety.
It’s not a big deal since many vehicles don’t have these systems, but you will lose a high-tech safety feature that your vehicle is supposed to have.
And in most cases, that’s all that happens when your ESP BAS light is on. However, a faulty sensor can cause further issues or even loss of additional safety features, so it’s best to do a proper diagnosis and go from there. Finally, not all vehicles have these advanced features, but yours may.