E34 525i Coolant Problem

[rml612]

My father gave me his 1990 525I, it is in excellent condition except for 2 problems.

The first is I get a coolant level warning. I checked the coolant level and it is full so I am guessing the coolant level sensor is bad and needs to be replaced. Question is, will I have to remove the coolant to change the sensor?

Second, intermittantly, I get a brake light warning, however the brake lights are fine and come on when the brake is depressed. The cruise control will not work when this happens. Could it be a bad brake light switch, and if so, where is located and how difficult is it to replace?

Thanks in advance for your help!

[2MuchTorque]

The coolant sensor may not be bad. Try this first:
From underneath the car, remove the wire terminal from the sensor. Use a small piece of fine (120-220) sandpaper to remove any corrosion from the copper terminals. This worked for me. If you do need to replace the sensor then yes you will have to drain the coolant. Be sure to get a new oring for the sensor.

[rml612]

Originally posted by 2MuchTorque@Jan 25 2005, 11:50 AM
The coolant sensor may not be bad. Try this first:
From underneath the car, remove the wire terminal from the sensor. Use a small piece of fine (120-220) sandpaper to remove any corrosion from the copper terminals. This worked for me. If you do need to replace the sensor then yes you will have to drain the coolant. Be sure to get a new oring for the sensor.

[snapback]278780[/snapback]

Thanks, I'll try it.

[da_bull]

One thing also, if the temp gauge is above the halfway mark at all, you have a problem somewhere else. As long you can drive it around with the gauge in the proper place, the sensor may be bad. Mine was slighty off center during a 60 mile trip, and that trip cost me a warped head to the tune of about 2300.00. My advice: dont take the cooling problems lightly. da_bull-----> ghead