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E12, E28, E34, E39, E60General discussion and technical help for all year 5 series cars.
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Your Ride: 2003 540I Sedan (M-Sport)
2003 E39 540 - Low Coolant Alarm
Hi Everyone,
Trying to get an idea of what to check.. Low coolant alarms since last year.. No indication of leaks.. We were messing around last year in "test mode" i think for the driver side cpu.. As posted previously this car isnt really driven alot nor hard.. Ideas on what to tackle first? Coolant sensor?
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Your Ride: 1994 540i
Try disconnecting the wiring for the coolant level sensor at the reservoir. If the coolant level in the reservoir is at the proper level and the coolant alarm deactivates, the sensor may be defective. Conversely, if the coolant alarm is still activated there may be a "short circuit" in the electrical wiring.