Continuous red luminous central latch

Hello Phateonists, if I tie my Phaeton with the key, then the central lock will flash several times and then it will light up permanently red instead of flashing. After about 1 min. the central lock will flash back normal. Doors are slashed. Battery in the key is still full, the green indicator light will still light up every time you act on it. First wanted to ask me here whether the safety guard has one off or what else it could mean before I take it back to the friendly and take it apart again the whole wire harness for my small change. Greetings from the coast