Low coolant level issue

[akos512]

Hello.

When I start my Leon (1.8T) and its cold, then i hear 3 beeps, and the flashlight at the temp gauge is blinking.
I read thats meaning the low coolant level, but its normal.
G52 was replaced, and there is no fault code in the ECU.
I measured the resistance between the 2 pins on the expansion tank and the resistance starts drop from ~450 MOhm to 0 than going up to 5-600 MOhm. Is that value normal?
Or what is the normal resistance on the Coolant level sensor?

 

[mty12345]

Scrape the 2 pins inside the expansion tank with a screwdriver or wire brush mate. Common problem, it's just a (almost invisible) build up of residue.