Tunze 6055 light blinking

[Gargamel35]

I have a Tunze 6055 pump. It's working ok, but the last time i connected power to it, red light at pulse is not on constantly. It's blinking. What does that mean?

I have another 6055 and two 6095s and all are on the same setting. Red lights are on constantly.

I cleaned the pump, it's working ok, but this light annoys me since i don't know what blinking means?

 

[rvitko]

This will mean that at some point or accidentally, the pump was set up in inverse mode and tied to another pump, to change this, set it to external mode and press the food timer button for about 2 seconds, this should get it out of inverse mode.