low coolant light

Hello,

the coolant level sensor is in the reservoir here is a video on how to change it on a similar car with a diagrams below to show you on your car.

https://youtu.be/4K-OifIw0cM

Check out the diagrams (Below). Please let us know if you need anything else to get the problem fixed.

Cheers

Why does my low coolant light come on after I have been driving awhile. There is no leaks and coolant reservoir is full.

it could be a short in wire that is hitting something or the coolant level sensor may be bad.

Low Cooland Warning Light comes on after startup, usually goes out after driving 3 miles, but lately coming on after I have been driving ten or so miles. (Engine is warm).

Have had the sensors replaced three times by BUICK dealership, new water pump, and radiator flushed at about 100,000 miles.

Now it is doing it again. Coolant level and water level is fine. No leakage noticeable.

What is the problem. I have already spent a good deal of money on this problem.

Take it back to the dealer. I wouldn't pay them to not fix my problem. Simple, you paid them, they need to fix. Take it back to them and insist it be done at their expense. After all you already paid them.

I have only had this car about a week. Even during the test drive, the low coolant light would flash on and off. I also noticed that the car heats up a bit more than it should...up to the half way mark or just a hair over. I have replaced the radiator cap (seals were deteriorated). The hoses (even when the car is running) don't seem like they are fully pressurized. Is it possible I have a bad water pump, and if so, could that cause my low coolant light to illuminate due to the lack of pressurized flow through the system? The car does run a bit rough now and again, and is sometimes hard to start. But the coolant level and overflow reservoir are full to their specified levels.
There is no coolant in the oil, and I am not smelling any through the exhaust.
Please help! Thank you.

I would suspect the level indicator is causing the light to come on. The engine coolant level indicator in located on the passenger side of radiator and the only fix is replacement.
Theses engines have a history of having lower intake gasket leaking.
As for testing, special tools are needed to pressure test the cooling system for leaks or the radiator cap to ensure the system is sealed so the system can maintain operating temperature (which also raises the boiling point in a sealed system).
Make sure nothing is blocking the radiator restricting air flow.
Start with the level indicator sensor my resource calls it a "engine coolant level indicator module".

low coolant light on with high coolant level, engine temperature shows increasing fast even just drive for 1 mile

does the car have serious coolant leak or something? thank you!

If you don't have an actual leak and the temperature gauge going to the danger zone-find the thermostat and replace it, then comeback for more when needed

The low coolant light comes on and goes off. The resorvoir is full. I do not see any leaks under the car. The engine temp is cool.

I would check the low coolant level sensor. Sometimes if the light is on you can tap the sensor. If the light goes out you need to change the sensor.

Can you tell me where it is located

It is located on the radiator just below the filler neck. Should have a three wire connector and its cliped on the radiator

Engine Cooling problem
2001 Buick Century 6 cyl Two Wheel Drive Automatic 94,ooo miles

You answered my question about the "poop" in the
cooling sustem,but what I'm really concerned is the
Low coolant light will not go off even when driving
after good warmup. The system is not low on water.
It does not overheat even in this texas heat. Would the light go off if the system was flushed as you suggested

The low coolant light sensor is in the right side radiator tank. Check out the images (below). Let us know if you need anything else.

I have the same problem, I drove with anti-leak (or as you call it "poop") for 6 months without knowing that it was there, I belive it messed up my sensor and now the light wont stop flashing. I did get everythnig flushed and nicely cleaned though. After that I just ignore it.

low coolant light keeps turning on and off when driving! but car is not overheating

maybe sensor is bad? you could just ignore it?

Don't confuse the low coolant light with an overheating light. They are not the same. Make sure the radiator itself is not low on coolant.

My low coolant light comes off and on but I have coolant in there the car is not heating up. I had the radiator flushed about 6 months ago and the water pump changed 2 weeks after that. My air conditioner heater does not work so my mechanic fixed it so that cold air would not come out right now in the winter. Hot air does come out a little sometimes even if the heater is not turned on. The car gauge is not showing that the car is heating up. I just 3 days ago had the coolant sensor changed 2 days no light but now the light came back on. The mechanic showed me that there was a little thick goo in the sensor. What to do now

check the switch in coolant tank

Engine Cooling problem
2000 Buick Century 6 cyl Automatic 75000 miles

when I start the care the low coolant light comes on for a while when the engine warm up it goes off.
the coolant level is good I tried a new radiator cap did not work

suspect faulty / sticking coolant level sensor, at bottom of overflow tank.

The car is a 99 buick century, 3.1 ltr. I just replaced the coolant temp sensor, throtle position sensor and the idle air control valve. I replaced the thermostat with the proper 195 degree replacement and refilled the coolant to proper levels and bled the cooling system. Occasionally we are still getting the LOW COOLANT LEVEL LIGHT. It flashes for 3 times. sometimes 4 groups of 3 flashes and sometimes 3 groups of three flashes. The light remains out at start up but comes on with the temp guage reading 3/8 ths. This has always been the normal reading on the temp guage though. I have double checked the coolant levels in the overflow tank while hot and in the radiator while cold. I know the thermostat is woorking properly because the upper radiator hose has fluid flowing through it at approximately 196 degrees.( this is the hose that goes from the radiator to the thermostat housing)

That light only measures one thing and that is coolant level in the radiator. If your sure the coolant level is full, then you likely have a bad sensor. They fail quite often.

I have a condition where the low coolant level light is coming on but the levels are good - hot and cold - and I can detect no leaks.

I checked the oil and there is no coolant in the crankcase, and seals have been replaced previously (which is a long term problem with this engine due to seal degredation from DEXCOOL antifreeze.)

The condition is only apparent after approximately 10 minutes of 55mph + driving on the interstate. Light will then stay on until the car comes to a stop at which time it turns off.

I suspect a faulty sensor but was curious of any other opinions before I pursue that route.

Thank you.

replace the radiator cap and clear out the line from the radiator to the coolant overflow reservoir. sounds like the radiator is not feeding from the overflow jug when warm.

i also put in some stop radiator leak!

Like mud? Do you mean contaminated with coolant?
Which engine do you have?

3.1L SFI OHV 6cyl

You didn't answer the question about coolant in the oil but I'm assuming you do. With that engine you likely have a bad intake manifold gasket, very common. DO NOT drive it or even start it up in that condition.

my low coolant light is flashing and the systom is full

it may be a shorted wire or a bad sensor.