Coolant light goes on and off - BMW Forum

dslim88 · 08-21-2008, 03:57 PM

On my 2000 BMW 328Ci manual the coolant light comes on while idling...when I reach about 40 mph or so it goes out and then comes back on when I stop then goes back out again when I reach about 40mph. The coolant level is fine. This all happened after the expansion tank failed and I replaced it...so the coolant level sensor is new. I'm going to buy another sensor anyway, but I was just curious if this could be something else. Thanks for any info.

darkhorse737 · 08-22-2008, 10:12 AM

coolant sensor connector not correctly fastened... loose?

dslim88 · 08-22-2008, 12:02 PM

Yeah I thought of that too... I disconnected it pulled it out and reconnected it...no luck.

darkhorse737 · 08-23-2008, 09:24 AM

pull out the connector and place a paper clip across the pins... lights out?

If yes, then coolant sensor is stuck or gone bad.

If no change with paper clip attached and stand alone... then it might be a wiring prob.

Good Luck.

dslim88 · 08-25-2008, 09:06 PM

Looks like the sensor is bad...thanks for the tips!!!