2003 BMW Z4 Repair Question
2003 BMW Z4 coolant light coming on after replacing thermos
2003 BMW Z4 6 cyl Two Wheel Drive Automatic 54000 miles
After we replaced the thermostat on my 3.0i Z4 the coolant sensor light will come on intermittently usually on the freeway. The light will go off after getting off the freeway and the temp gauge never indicates anything other than normal. The coolant level is full but the light continues to come on.
Hi BrianZ4 and TY for the donation
Check and test the coolant level sensor, also be advised you have a coolant temperature sensor for the computer and an engine temperature gauge switch for the engine
Service and Repair
Replacing Level Switch For Coolant
Loosen screws (1).
Raise expansion tank (2) slightly.
Installation: Insert locating pin (1) into locating bore (2).
Disconnect plug connection (1).
Turn coolant level switch (2) approx. 90 °in direction of arrow and pull out.
68 questions asked
It is possible the expansion tank is the culprit and will require replacement. The float that commands the light on is possibly faulty, and/or the reed switch.
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