Audi Central Locking Malfunction: What Should You Check?

The Central Locking System is one of the great automotive wonders. This system significantly improves user comfort and safety by not having to unlock every door manually, which is great, especially when you're in a hurry.

Simply twisting the key in the driver's door is enough to lock the car. Later, with the introduction of key fobs, things have become even easier to operate. The only thing you had to do was press a button on it to lock or unlock the car, so this meant no more returning to it to double or triple-check that it is locked.

This system is something that most drivers out there take for granted, but as soon as it stops performing as it should, every trip suddenly becomes a lot more stressful. Even though the Germans are known for making some of the most durable vehicles out there, they can develop faults from time to time.

To be more specific, we're going to talk about why your Audi's Central Locking System, or CLS, fails, how to fix this problem and how to avoid it in the future.

Why does the Central Locking System fail?

Audi is no different from other manufacturers when it comes to the CLS, so most of the things that could cause problems can occur in other vehicles as well. Some of them, however, might be specific to certain manufacturers. Here are some of the things that could cause trouble:

• Active child locks

While this might seem a little bit obvious, it is worth checking that the child locks are not faulty, since they might remain in the locked position and cause the doors to not open. This is something that might only happen on the back doors since the front ones usually don't have this kind of safety feature.

• Blown fuse

A blown fuse means that a certain system will stop working, so it is one of the first things you check, regardless of what vehicle electrical system we're talking about. The reasons fuses blow is because of too much resistance, or to protect circuits and modules from a power surge, so if the fuse blows again, the issue might be somewhere else.

• Bad key fob battery

With time, the battery on the key fob will eventually run out, which will cause the key fob to stop working as it should. If you can open the doors mechanically, this could be what's causing you problems. Also, key fobs have little LEDs on them that light up whenever you are pressing a button to indicate functioning, so keep an eye on this aspect.

• Key fob desynchronized

Even if you don't do anything to mess with the key fob or with the software of the car, after a certain period, the key fob might desynchronize with the central locking. The procedure for synchronizing a key is usually different for every manufacturer, but for the Audi model that is concerning you, the process should be easy to find on the internet or in a good service manual.

• Faulty key fob

Much to no one's surprise, electrical components do fail after some time, so don't be too surprised if this were to happen to you. In this situation, the vehicle might not even start, since the car's immobilizer will probably not recognize the key fob and will therefore prevent it from starting.

• Software needs an update

As you might already know, modern cars have loads of electronics in them that make our lives easier, but whenever they stop working as they should, they can become really annoying. Fortunately, since they are so clever nowadays, many issues can be fixed by simply updating certain modules.

If that's the case, your local Audi dealer will probably tell you this as soon as you describe your issue. Keep in mind that there has been a recall for certain Audi models manufactured between 2019 and 2020, regarding this specific problem, so if your car fits in this category, it's worth paying the dealer a visit.

• Bad vehicle battery

A bad battery will almost always cause electrical issues, so if nothing else seems to give positive results, it's worth checking that the battery is good. If it is already more than 5 years old, we would advise you to change it anyway.

• Water intrusion

This is something that you will want to check since it can do a lot of harm to pretty much any component it will get to. Bad door seals, vapor barriers, and so on, will almost always end up in water making their way into places they shouldn't. Also, this issue alone could be the reason that one of the problems that we mention next has made its appearance.

• Components lacking lubrication

While they are controlled electrically, door locks are still mechanical components, the only difference being that there is no need for any mechanical input to lock them. If you are quite handy when it comes to DIY stuff, you could take your time and lubricate everything, since you won't do any harm even if you don't fix the issue this way.

• Faulty door actuators

Electronic door actuators are known to go bad after some time, so this is not a rare phenomenon in any vehicle. They usually don't fail all at the same time, so you might find that only a certain door has issues when it comes to locking and unlocking.

• Interrupted wiring

One of the least fun problems to diagnose would probably have to be bad wiring since it usually takes quite a lot of your time. Sometimes, the quality of the wires simply isn't as good as it should be, which usually results in split wiring. This isn't the only reason that could cause them to fail. With age, and if exposed to heat or humidity, the wiring will become a lot more fragile, so keep this in mind as well.

• Faulty door control module

The door control module's job is to deal with everything related to the doors, in this case, the CLS. Should it fail, you will probably not be able to operate the system as you normally could.

• Faulty comfort module

When this happens, issues won't be limited to just the central locking, but also to things like electric windows or the sunroof, in which case, the problem will probably be quite obvious.

How to repair the Central Locking System?

As you've already seen, some of the issues presented above can be easily fixed by any DIY enthusiast at home, but some of them require specialist help. When it comes to messing with the electronics of the vehicle, we would strongly advise you to pay a visit to a specialist or to your local dealer.

Audi is known for having quite complex electronics and one simple mistake could end up in an electrical nightmare, especially if we're talking about a newer model. A great advantage when it comes to newer vehicles is that performing a diagnostic will usually tell you if a certain electronic component doesn't work properly, making the problem easier to diagnose.

The simple stuff should be no problem, especially since the procedures mentioned are thoroughly described on the internet and in service manuals, and the chances of you causing more harm are very low.

The bad news is that if certain electronic components need replacing, things might get expensive. They are usually not easily serviceable and most of them come as a whole assembly. The good news is that some components are widely available on the used market, so if the price is way lower than the new alternative, it is definitely worth giving this solution a try.

Keep in mind that if we're talking about modules that need replacing, coding might be necessary. This can be done by most Audi specialists out there, with dedicated tools.

How to avoid issues with the Central Locking System?

Unfortunately, there's not much that you can do to prevent failure, other than greasing components after a few years and making sure that your vehicle and key fob batteries are always in good working order.

However, there's no need to worry, since there is also little you could personally do to cause problems. This doesn't mean that these components will take abuse like it's nothing, so we would advise you to always be gentle, regardless of what system you're operating. Also, checking and cleaning the water drains of the car is good practice too.

Final thoughts

As useful as the Central Locking System can be, it can quickly become a real nightmare if it stops working properly. Usually, most people decide to deal with this problem as soon as possible, since there have been several situations in which the vehicle couldn't be locked, thus becoming a potential target for thieves.