The spring is missing or bent

The contact springs are screwed into a nut like a screw, which is located in the connecting socket.

1) To replace a bent spring, turn it counterclockwise out of the socket with your thumb and index finger.

2) Remove the colored spring retainer with a pointed object (screwdriver, flat-nose pliers, etc.).

3) Screw the new contact spring with the tightly fitting coils first 4-5 turns clockwise into the connecting socket.

4) Then check that the spring is firmly seated in the thread by pulling gently on it. Be careful not to overstretch the spring.

5) Then insert the spring retainer into the socket via the contact spring. Note the two colors of the spring retainers: Blue sits in the tube side with the size sticker, red in the other side.

Now gently press the bushing against a flat surface to fully press the spring retainer into the bushing. Make sure that the contact spring is not kinked or bent in the process.

6) Repeat the insertion of the spring on the other side of the tube.

7) Insert the two ends of the light tube one after the other straight into the battery compartment. Be careful not to bend the contact springs.

8) Press the battery compartment and the tube firmly together on both sides as far as they will go. IMPORTANT: There must be no gap between the battery compartment and the tube:

Notice:
The spring retainers have two functions: On the one hand, they ensure that the spring is aligned with the center of the battery pole, and on the other hand, they indicate by color how around the light tube and the battery compartment must be connected.