Coolant Warning Light!

Ian Fearn · Post by **Ian Fearn** » 03 Jan 2005, 22:08

Having just sorted out my cooling system with new rad, fan switch and obviously new coolant the engine now runs loads cooler and the fan cuts in at about 90 degrees and cools the engine down nicely.
Everything was great until last night when my coolant warning light came on. Coolant at 28cm from filler neck. It didnt do it this morning when started until it got warm and its been constantly on ever since. Temp guage still showing what it should.
Does anybody else think its narrowed down to a broken coolant level sensor?

oilyspanner · Post by **oilyspanner** » 03 Jan 2005, 22:54

I think the sensor is just a pair of contacts which should be immersed normally, low coolant breaks the circuit and activates the lamp, try removing the connector and perhaps bridging the contacts, this should make the lamp go out, if it does not then the problem is elsewhere.
Stewart

dnsey · Post by **dnsey** » 03 Jan 2005, 23:30

IIRC, the BX coolant level switch is a float switch, consisting of a hinged float containing a magnet and a reed switch.
Try unplugging the sensor connector and shorting the contacts to check it.

Ian Fearn · Post by **Ian Fearn** » 03 Jan 2005, 23:33

I didnt think there was any float on it, just 2 prongs.
When you disconnect the level detector on an otherwise working car the light comes on the dashboard hence the reason i think mine maybe knackered.
If it is dead then bridging the contacts wouldn't make any difference would it?

oilyspanner · Post by **oilyspanner** » 03 Jan 2005, 23:50

Older models had the float assembly, later it was replaced by a pair of contacts (just as well I couldnt get the float ones out without breaking em)bridging the contacts would make the light go out provided no other problems, I have cleaned the contacts on these before, covered in limescale.
Stewart