Brakes 1990, low coolant light riddle

bdemat

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Sep 22, 2018
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Acworth ga
Hello everyone, riddle me this, I have a 1990 5.0. Low coolant light always coming on. Coolant is fine, constantly checked it to make sure. Replaced the low coolant sensor twice with new lmr one. Replaced the connector, still on. When I unplug the sensor light goes out. It's not usually on when I just start the car but it will come after a mile or so
 
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i just unpluged mine and check it with all my fluids once a week.i mean do we really need an idiot light?whats next sensors telling us to check our air in the tires?another one to tell us to change our oil?,put our seatbelts on?At this rate the cars will be driving themselves!
 
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Thanks guys for the advice but I am the type of person that has to have everything work the way it's supposed to. I know it's not that big a deal but I will mess with it a little longer to figure it out.
 
Thanks guys for the advice but I am the type of person that has to have everything work the way it's supposed to. I know it's not that big a deal but I will mess with it a little longer to figure it out.

I'm the same way so I understand your plight. Usually it is the sensors but as a check you can check the wiring to make sure it's in good shape. Red will be your power and black is the ground. With engine on make sure you have a consistent 12v here. The blue wire is your return to cluster. Closing the sensor (low coolant) will trip the light which is why unplugging it will keep light permanently off
 
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This for an 89 and may be hard to read, it shows how to test the circuit, wire colors ma be different but it will give you an idea of what to look for, hope this helps
i like stuff to work right too!
 
I'm the same way so I understand your plight. Usually it is the sensors but as a check you can check the wiring to make sure it's in good shape. Red will be your power and black is the ground. With engine on make sure you have a consistent 12v here. The blue wire is your return to cluster. Closing the sensor (low coolant) will trip the light which is why unplugging it will keep light permanently off[/QU
I'm the same way so I understand your plight. Usually it is the sensors but as a check you can check the wiring to make sure it's in good shape. Red will be your power and black is the ground. With engine on make sure you have a consistent 12v here. The blue wire is your return to cluster. Closing the sensor (low coolant) will trip the light which is why unplugging it will keep light permanently off[/QUO
 
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I will test that and see what happens, Thanks for the help and the pics!
Did you resolve the low coolant light yet? My 91 LX exact same. New radiator. New sensor and pigtail connector from LMR. Coolant levels in both the XS bottle and radiator look fine. No leaks. Not overheating. But low coolant idiot light is on and stays on. I’m tempted to disconnect the sensor and live free. How much more nonsense does Ford want us to go through ?
 
Did you resolve the low coolant light yet? My 91 LX exact same. New radiator. New sensor and pigtail connector from LMR. Coolant levels in both the XS bottle and radiator look fine. No leaks. Not overheating. But low coolant idiot light is on and stays on. I’m tempted to disconnect the sensor and live free. How much more nonsense does Ford want us to go through ?
Yes and
Did you resolve the low coolant light yet? My 91 LX exact same. New radiator. New sensor and pigtail connector from LMR. Coolant levels in both the XS bottle and radiator look fine. No leaks. Not overheating. But low coolant idiot light is on and stays on. I’m tempted to disconnect the sensor and live free. How much more nonsense does Ford want us to go through ?
Yes and no. I found the ground wire coming off the connector plug and grounded it to the frame. The light stayed on for about two or three days after that and then I haven't seen it since. Don't actually know if that fixed it or if it's just went out. Either way it's gone.
 
Yes and

Yes and no. I found the ground wire coming off the connector plug and grounded it to the frame. The light stayed on for about two or three days after that and then I haven't seen it since. Don't actually know if that fixed it or if it's just went out. Either way it's gone.
Thanks for this post! I followed the ground route and wal lah fixed as well!!