Parking aid defective: What to do if it no longer beeps

 

Cars are getting bigger, longer, and wider. In short: more confusing. Especially in inner-city areas, parking often becomes a problem. To ensure that the vehicle still drives quickly and consistently into the narrow parking space, most new cars now have parking aids on board, so-called "parking beepers". But what if the system does not work properly, or even gives misleading signals? Our guide clarifies which errors can occur with the parking aid and which you can fix.

Car manufacturers often use their own names for the parking aid, or the "parking beeper". Most companies, including BMW, refer to it as PDC (Park Distance Control). At Audi, the system is called APS (Acoustic Parking System), Volkswagen calls it "Parkpilot". They all beep when parking gets tight.

Parking aid defective: Dirt or ice can also paralyze the PDC

If Park Distance Control (PDC) is no longer working properly, there are several possible reasons. One or more sensors may be defective or give false alarms. The latter often leads to a continuous beeping after engaging reverse gear.

Before you assume the worst, a defect in the system, you can try to solve the problem yourself with the defective parking aid.

In summer, it is not uncommon for dust or dead insects to settle on the sensors after long motorway journeys. In winter, a layer of ice or snow may have formed and impair function. In these cases, you should carefully clean the affected sensors with a soft cloth.

Often, even a small parking bump is enough to damage a sensor. Often a plug on the sensor is damaged in the process. You can tell by the fact that a sensor is no longer exactly in the intended hole in the bumper, but in or even behind the bumper.

If a sensor is defective, the bumper must be removed

If neither dirt nor a parking bump are the obvious cause of the fault, the bumper must be dismantled.

If the PDC emits a continuous tone, you should first examine which sensors work and which don't. To do this, apply the handbrake and engage reverse gear. Then you listen to each sensor. If you hear some kind of continuous clicking as soon as you gently swipe your finger over the sensor, it works. If you don't hear this click with one or more PDC sensors, you know which parts are defective. They have to be replaced.

To repair the sensor, you must first loosen the bumper. To do this, disconnect the cable of the PDC control unit, which is usually installed in the trunk behind one of the two side walls. Only now can the bumper be removed - preferably in pairs. If the bumper slips out of the hand, intact sensors can be damaged.

Incorrect alignment of a sensor leads to malfunction

If the bumper is exposed, the defective PDC sensors can be pulled out of the holes to the rear and removed from their connectors. Now you can put the new sensors on the plugs. It is essential to pay attention to the orientation. A PDC sensor that is not placed correctly will not work properly later. As a result, the parking aid sends the wrong signals – for example, after reversing gear is engaged.

Before it can be glued on, it must be cleaned. To do this, old adhesive residues, dirt and moisture must be carefully removed. Then let the areas dry. Then you can carefully put the new sensor plate on without pressing it firmly yet. If the sensor is exactly in the hole, you can press the plate firmly.

Parking aid defective: YouTube and some forums on the Internet can also help

Once you have routed the cable for the control unit through the hole in the body, you can put the bumper back on and attach it. Now run the cable to the control unit and connect it via plug.

The Park Distance Control should now work perfectly again. If it does not work, the car's fault memory may have to be deleted in a workshop.

Defective parking aid: Other causes

Of course, the fault can also lie elsewhere than with the sensors. The control unit may be defective or a cable break may cause a malfunction.

The search for such a fault would be better taken over by a specialist. The reason: Most drivers do not have access to the corresponding test equipment. The costs depend on what is defective – sensor(s), cable or control unit – as well as on the amount of work. Replacing a sensor in the workshop should not cost more than 100 euros. If the control unit has to be replaced, the prices are higher.

Parking aid defective: Replacing the PDC sensor – This is how it works

• Locate the affected sensor
• Loosen the bumper
• Disconnect/disconnect cable/connector from the control unit
• Remove the bumper – if possible not alone
• Pull the defective PDC sensor out of the bore to the rear and disconnect the connector
• Plug in a new sensor, pay attention to the orientation
• First clean the area where the sensor plate is to be glued
• Carefully place the sensor plate with the sensor, do not press it down yet
• Check whether the sensor is exactly in the hole
• Press firmly on the sensor plate
• Routing cables through the body hole
• Put the bumper on and screw it on
• Connect the cable to the control unit via plug
• If necessary, have fault memories deleted in a workshop