Locks

How to open the safe when the battery is dead

3 min read

An electronic lock requires power. If your safe emits several consecutive tones after you enter your code, the battery is low. You then have about 30 more openings left. If the signal is ignored, the safe can still be opened, just in a different way. Exactly how depends on the lock.

First

Which lock do you have?

The two locks are opened in completely different ways. Before you loosen anything, look at the control panel on the door:

Electronic Stellar combination lock with numeric keypad on the safe door — **Numeric keys visible:** Stellar series combination lock. Continue under Stellar Combination Lock.

Kaba Mauer Combi lock with round cover cap on the safe door — **Round cover cap:** Kaba Mauer Combi. Continue under Kaba Mauer Combi.

You can perform both procedures yourself; you do not need any special tools. If you get stuck, call us before you try to pry anything open.

The Basics

Why the battery fails in the first place

An electronic combination lock is powered by a battery. Therefore, the input panel and the locking mechanism depend on electricity. These components consume very little energy, which is why a battery charge usually lasts more than 3 years. Depending on the frequency of use, we recommend changing the battery once a year if it is used heavily. Only use high-quality brand-name batteries! Our years of experience have shown that cheap batteries often have a shorter lifespan and weaknesses regarding the required voltage.

When the battery charge is running low, the lock will alert you with acoustic signals. If you hear several consecutive tones after entering your code to open the lock, this is the signal to replace the battery. You then have approximately 30 opening cycles remaining before the lock refuses to open due to a lack of power.

Stellar Combination Lock

Recognizable by the numeric keypad. Power is provided externally via a 9-volt block battery.

Video tutorial for the Stellar combination lock. The procedure below applies to the Kaba Mauer Combi.

You will need

A 9-volt block battery
A screwdriver, or alternatively, a dull knife

How it works

Loosen the numeric keypad on the left and right using the screwdriver
Carefully pull the keypad out (there is about 3-5 cm of slack in the cable)
Connect the block battery to the contacts on the back of the keypad
After about 10 seconds, a ready signal will sound from the keypad.
Open the safe as usual using the numeric keypad
Disconnect the battery from the keypad and replace the battery inside the door.
Push the cables back and reinstall the keypad.

Loosening the dial of the safe combination lock with a screwdriver

Connecting a 9-volt block battery to the keypad contacts

Opening the safe via the keypad using emergency power

Changing the battery

Once you have managed to open the safe, you should replace the battery in the battery compartment so that the safe can be opened normally again. To do this, locate the battery compartment. It is located inside the door. Once you have found it, open the cover, remove the dead battery, and connect the new one. Test the functionality with the door open. If an opening and closing cycle can be performed without problems, you have successfully changed the battery.

Battery compartment on the inside of the safe door

Inserting a new battery in the safe and checking functionality

Kaba Mauer Combi

Recognizable by the round cover cap. It is not powered from the outside; instead, it is opened via an emergency key.

The emergency key access and the battery compartment are located under the cap. The marking on the lock carrier indicates the direction in which to slide.

Loosening the cover cap of the Kaba Mauer Combi with the included tool — Step 1

Remove the cover cap, beneath which appears the indication to slide for battery replacement — Step 2

Inserting the emergency key into the exposed opening — Step 3

Emergency key inserted into the Kaba Mauer Combi, marking to slide for battery change — Step 4

Loosen the cover cap. The round cap in front of the lock is loosened with the included tool. It is firmly seated, but does not require force.
Remove the cap. Beneath it, the lock carrier is revealed. The marking indicates the direction for the battery change.
Insert the emergency key. The key is inserted into the exposed opening.
Open and replace the battery. This also uses a 9-volt block battery. It is replaced in the same way as with the Stellar: disconnect the old one, connect the new one, and check the functionality with the door open.

Connecting a new 9-volt block battery and checking functionality — The battery replacement process is the same for both locks.

Do not keep the emergency key inside the safe. That sounds obvious, but it happens regularly. The emergency key belongs in another secure location; otherwise, it will be right where you cannot reach it in an emergency. Recommendations for this can be found under Secure Key Storage.

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Frequently asked questions

How do I know when the battery is running low?

After entering the code, you will hear several consecutive beeps. You will then have about 30 openings left before the lock refuses to open due to insufficient voltage.

How do I open a safe with a Stellar combination lock?

Release the dial to the left and right and carefully pull out the keypad

And for the Kaba Mauer Combi?

There is no external power supply provided there. The round cover cap is removed using the supplied tool, underneath which are the emergency key access and the battery compartment. Open with the emergency key, then change the battery.

How often should the battery be changed?

One charge generally lasts more than three years. In cases of heavy use, we recommend changing it once a year, and only using high-quality branded batteries.

What should I do if the external power supply does not work?

Contact us before prying anything open. If only the dial is defective, it can be easily replaced from the outside. You can find all ways to contact our service team on our contact page.