2000 c70 Coolant light

hvymtlc5 · Post by **hvymtlc5** » 01 Jul 2014, 09:25

Need walk through of what to check next.

Car has 102K miles. Previous owner said he could not get the coolant temp light to go out and had replaced a lot of parts and gave up trying to fix. I just changed out the T-STAT, ECT, and the radiator (was leaking -needed replaced) but still have the temp light after resets.

For troubleshooting - sometimes the fan will stay on and run a few minutes if I just back the car out of the garage. Other times it does not. It does come on with the AC on. Temp gauge always runs just a little above half when car is warmed up.

I have read that low freon will even cause the light?? What should I look at next so i can get a little boost in the car since I believe the computer turns that off when there is a coolant temp light?

Post by **abscate** » 01 Jul 2014, 10:47

Is this the high temperature light or the low coolant level light (yellow, looks like a radiator).

The low coolant level light is triggered by a float in the coolant reservoir - easily broken and also easily replaced.

Post by **mikealder** » 01 Jul 2014, 10:47

Do you mean the low coolant alarm, if so check the float inside the coolant expansion tank is still floating, if it has sunk you need a new expansion tank as the float is an integral part of the tank. The low coolant sensor is a small reed switch that fits in to the base of the tank, if the float hasn't sunk I would try a new low coolant reed switch - Mike

hvymtlc5 · Post by **hvymtlc5** » 07 Jul 2014, 06:21

The light is the red radiator symbol

Post by **abscate** » 07 Jul 2014, 07:05

Im getting my model years and colors messed up, sorry.

Looking at the 2000 C70 manual I don't see a radiator cooling light but thats probably either a model year break or something else. Do you have the messaging system on the LHS of the dash ?

Either way, the radiator light on my 1999 indicates low coolant level - I think either the float is stuck or the sensor is bad. to replace the sensor - you don't have to drain the coolant - gently lift the coolant reservoir and unplug the sensor from the bottom.

Post by **jblackburn** » 07 Jul 2014, 08:28

Sometimes the float just gets stuck from crud inside the tank. If you can't see it bob around as you shake the tank, take it off the fender and whack the side of it with a wrench to free up the float. If that doesn't work, go for the sensor itself.

Post by **abscate** » 07 Jul 2014, 09:08

When you lift the coolant tank, the sensor connector is on a short leash. Lift a few inches gently, get your fingers under it and release the sensor connector so that you don't break an otherwise good sensor

Voice of experience, of course.