04 S80 Coolant Light Staying On

Kjmike95 · Post by **Kjmike95** » 21 May 2019, 13:42

On my 04 S80 T6, my low coolant light stays on. I would worry about it more, however, my engine temp is completely fine.I'll fill up the coolant tank and the light will stay on. What is worrying though is after a couple months, it looks like my tank is empty. I've checked the oil and there's no sign of coolant in my oil and it isn't leaking on the ground. What else might be worth mentioning is the heat doesn't work.

This is my first post, so this may be a common issue, but after looking around, I haven't found it.

Post by **RickHaleParker** » 21 May 2019, 14:07

There is a switch on the coolant reservoir tank that controls the low coolant light. Check that switch it's wiring and connector. Also check the float in the coolant reservoir tank, make sure it not stuck.

No heat could be a lot of things. You will need to get more information.

Post by **June** » 21 May 2019, 14:11

The light is likely the sensor in the coolant tank. Obviously you have a leak. Check the water pump, and all the hoses. Just this year I had one of the hoses to the oil cooler on the oil pan started leaking. Here I thought all the hoses were replaced and bam a coolant leak at the back of the oil pan... so if you have not replaced all the hoses you are passed due! June

Kjmike95 · Post by **Kjmike95** » 22 May 2019, 18:24

I just filled up the tank to half way. I did check the connecter, wires, as well as the float. I couldn't find the switch. Maybe I can be informed of what that is. I haven't checked the hoses for a leak yet, however the car has sat in the same spot for a couple weeks and there wasn't any signs of leaks.

Since the days have been 80°+ everyday, heat isn't a problem. Just thought it may be a symptom of something else related to the coolant low light.

Post by **RickHaleParker** » 22 May 2019, 18:44

Kjmike95 wrote: ↑22 May 2019, 18:24 I couldn't find the switch. Maybe I can be informed of what that is.

This is on a V70 but the S80 is the same. A new sensor is about $28.00.

[youtube][/youtube]

uncletom · Post by **uncletom** » 07 Feb 2020, 15:00

Mine came on also at 160,000 99 S80 . Just a faulty sensor plugs into the bottom of reservoir . Can unplug and pull out without draining reservoir . 30 sec. repair