Low Coolant Light...

[riffraff4201969]

Having trouble with the low coolant light. First some relevant history: Because I wasn't in town, my car sat for a about a month and had to be jump started. Prior to this time, car wasn't overheating. Afterward it was running hot--above what it did before normally--and giving a constant low coolant light. Since blower gave plenty of hot air, I figured it was the thermostat and not the water pump and I replaced it (OEM 190 degrees) and topped off the overflow tank to about an inch over the MAX line. It does not appear to be overheating now. However, when I turn her over now from a cold start the low coolant light initially flashes then goes off but after she warms up the low coolant light turns back on. I figure it's the coolant low level switch. The system is not leaking coolant. I'm going to inspect the switch to see if there is a connection issue or if it's fouled. Any other suggestions? Thanks.

 

[BrApple]

the system isn't leaking but is the fluid level in the overflow tank changing?

one of two things come to mind. head gasket or the radiator is becoming a balloon and holding coolant.

 

[TRicker]

run the car till hot. once it's taken its max, fill it to exactly the full line. it will be over full when the car is cold, but it will be full when warm. open the cap slowly obviously.

i had problems with that stupid light in the winter and such, so i just bypassed the sensor and it can't come on now. of course i always have my hood open so i know if its ever low

 

[riffraff4201969]

the system isn't leaking but is the fluid level in the overflow tank changing?

one of two things come to mind. head gasket or the radiator is becoming a balloon and holding coolant.

Well I ''topped it off'''--maybe two or three cups worth...a final adjustment following the thermostat replacement--to make sure and get the fluid level over the MAX line, since I know the low coolant level switch can be sensitive.

UPDATE: Now the low coolant light is on continuously.

Questions: 1. Does the low coolant level switch/light measure anything else, other than the coolant level in the overflow tank? In other words, does any other sensor trigger the low coolant light? 2. Is there a particular fuse that needs to be checked? (I've checked the Owner's Manual and Haynes and didn't see anything directly applicable.)