Audi Pre-Sense Malfunction – Top Causes

Pre-sense is a feature on Audi vehicles to help alert the driver of possible safety problems before they occur.

The working of the Audi pre sense is based on the sensors installed in the car.

If these sensors detect any obstruction, it will give a warning to the driver and start braking immediately.

However, despite Audi’s best efforts, sometimes their technology fails to react appropriately in time.

But, what could be the cause of such a critical system malfunctioning in Audi?

So before you think of any procedures to restore the system or try to figure out anything.

Read ahead for the possible causes of the system malfunction and their immediate solutions.

Causes Of Audi Pre Sense Malfunction

Most people find it unbelievable that the feature meant to aid their driving changes the car’s behavior. Well, worry not, here are the common problems behind it.

Faulty Pressure Sensor Or Recalibration Issues

A pressure sensor determines the current tire pressure in each tire. It is done so that an Audi Pre Sense system can determine if a tire is low on air.

It will allow the car to react accordingly. When it is not working correctly, it will not be able to provide the correct information to your car’s computer.

Therefore, it could cause the computer to react incorrectly and suffer your car’s performance. Your car will probably not respond to the brake pedal at all.

It will also be harder for you to stop because of the lack of pressure.

Solution

You may need to let a mechanic test and calibrate the sensor for you. If you have recently rotated your tires or changed them out, it can happen.

It could be because the change may have affected how the tires are positioned. Thus, affecting their interaction with other parts of your vehicle.

Corroded Or Damaged Brake Lines

In some cases, your Audi Pre Sense may have corrupted or damaged brake lines that need replacing.

It will prevent them from being able to respond as they should when you are trying to stop your car.

For example, when braking on a wet road, it’s normal for a vehicle to skid just a bit before stopping.

In such situations, the Audi pre-sense system uses advanced sensors to detect a potential skid and applies brakes automatically.

It helps you maintain control over your vehicle. But, the broken brake lines will affect the information read by the sensors, causing a malfunction in the system.

It could lead to a serious accident if the brakes do not work correctly.

Solution

A mechanic will be able to replace these lines with new ones that are designed specifically for your model.

You have to make sure the lines match your vehicle’s model for them to last longer and perform better.

Flash Memory Failures

The main reason for this problem is a faulty flash memory module. The module controls the Audi Pre-Sense and City Emergency Braking systems.

If it fails, it can no longer communicate with other parts of your car. It can cause many problems, including the Pre-Sense malfunction message.

If you disconnect the vehicle’s battery for several minutes or longer during a service visit, the issue can occur. It made the flash memory to be corrupted.

If not addressed, faults with the tire pressure monitor active lane assist will result in faults.

It will also fault other systems that rely on sensor information from the pre-sense control unit.

Solution

You will need to update your vehicle’s Engine Control Unit to resolve this issue.

The update has to be with the latest version of the software using an ODIS Service diagnostic tool.

Audi has now implemented a software update that they must implement on all affected vehicles to avoid this issue.

It should, however, be before disconnecting the vehicle’s battery. Without the update, technicians may need to replace the engine control module.

Short Circuit

A faulty wire causes the malfunction under the passenger seat. The wire carries 5V to a sensor that triggers the airbag in a frontal collision.

When this wire gets pinched, it causes a short circuit that trips the Audi Pre Sense system.

The short is also caused by water leaking into the fuse box where all that wiring comes together.

It could also be caused by a bad connection between two wires in that harness (such as due to corrosion).

Even just a loose wire that isn’t making good contact with its connector can be the trigger behind the malfunctioning.

Solution

You can fix this issue by replacing the wire harness and cleaning all the wires.

Excessive Dirt On Radar (Sensors)

There needs to be adequate space around the radar electronics to work correctly. The space will aid in detecting vehicles at greater distances.

If there is too much debris or other excessive dirt on the radar, it causes signals to become confused. It further triggers pre-sense by accident.

Solution

Turn off your daytime running lights and any other lights to see if that helps prevent it from activating.

To avoid these problems, make sure you service your vehicle once every six months and check your bodywork regularly.

If you see any abnormal noises coming from your car, it’s better to have it checked before something worse happens.

Speed Differences Between Two Vehicles

The radar used for adaptive cruise control relies on the Doppler effect.

When a vehicle travels at high speeds and passes another, the targets’ relative velocity adds up over time. It produces an audible sound.

If the targets’ relative velocity is too great or too small, the system doesn’t register them.

It can lead to a “pre-sense” malfunction, where the system thinks there’s an obstacle ahead that’s causing it to slow down.

Solution

When overtaking or approaching a vehicle ahead, make sure the speed difference between the two vehicles is less than 35 km/h.

If the speed difference is higher, there are high chances of Audi Pre-Sense Malfunction.

The best way to overcome this situation is by adopting safe driving behavior.

You should not drive your car fast and keep in mind all the safety measures while driving on busy roads.

The same issue can arise when overtaking on a highway. If you try to pass another vehicle and speed up, its difficult for Audi Pre-Sense to detect their exact location.

It can cause the system to break your vehicle sharply, leading to an accident in certain circumstances.

Failure In Front Looking Camera

Pre-Sense relies on data from its forward-facing camera and radar sensors to detect whether there are stationary objects in front. The objects can be traffic lights or signs.

So if the front camera fails or spots several vehicles, probably when making a sharp u-turn, the computer gets confused.

The computer’s confusion is with its surroundings as it can’t decide what to do to avoid a collision.

Solution

It would be best to have the vehicle assessed and the front camera replaced. You, however, need to make sure all this is done by experienced personnel.

Audi Pre-Sense Malfunction – Conclusion

Finally, unlike other crash avoidance technologies like automatic braking, the Audi Pre-Sense system is not an entire autonomous safety device.

It can only apply the brakes in appropriate situations to limit some accident damage and reduce occupant injuries.

But it cannot prevent a crash or the resulting injuries entirely.