Low coolant level error on bmw f20 116i 2014 n13 motor

[decs55]

Dear all,

I am new here and would like to thank you in advance. I have seen this thread a lot of times but it seems that is for a older version with a different type of sensor at the expansion tank.

I do not have the magnetic float sensor type inside the expansion tank, when I disconnect the plug, I see two wires, one brown with a black line and another one black. I first thought okay I will measure continuity as I thought that when the sensors resistance drops, would close the circuit... I got no noise, I jumped the wire and also kept getting the signal.. so my assumption is that this does not work like a switch,,, (sorry I am not engineer, just enthusiast).. first question, do you know what this type of sensor is and what is supposed to be the two cables? signal from sensor and voltage?

I got an aftermarket expansion tank and changed the original bmw and I noticed that one pin was broken, see pictures.. with the aftermarket one, I still got the low coolant signal , but I noticed that it was leaking in one hose...

I ended up installing the original bmw expansion tank and I am not sure if this sensor can be bypassed or not?

do you think that the main issue with the original was the pin and that the main issue whit the aftermarket tank was that it was leaking?

how can i be sure that the cables are correct? do you know by any chance which reading I should be getting?

sorry for the dirty fingers! i was working with the car :P

all the best!