Low Coolant message

SnowOwl · Post by **SnowOwl** » 13 Sep 2017, 22:30

My 2003 S60 non turbo 5 cylinder started giving me a continual low coolant message, but the coolant isn't low. Since the coolant isn't low, I drive the car and keep an eye on the temperature gauge, and the engine never seems to get hot. This has gone on for several days. Where is the low coolant sender? How would I check it?

History, this car has had a tendency to overheat in stop and go traffic for about a year and a half. When I had the timing belt done, I decided to have the water pump replaced since mileage is about 175K and it never had a water pump replaced before. The repair shop told me Volvo recommends replacing the thermostat any time the engine overheats because the housing warps or something. There was also a little split in the coolant overflow tank so I had that replaced. A few weeks ago I got caught in bumper-to bumper stuff and the temperature gauge started climbing, so I pulled over 'til the traffic eased up. As long as the car is moving, the temperature stays in the normal range. Since this pointed to the cooling fan, I poked at it and found out the fan was locked up stuck and wouldn't turn at all. I replaced the fan. Everything was fine for a week or so, and then the Coolant low, Stop engine message popped up in pretty normal driving. I pulled over, the fan was not locked and the coolant was not low. I drove, and promptly got caught in a traffic jam, but the temperature never went above normal. I'm guessing the new fan works OK.

Is this coincidence and the sender just went bad, or am I missing something?

Post by **abscate** » 14 Sep 2017, 01:34

The coolant level sensor lives in the overflow reservoir. It sounds like it has croaked, snuffed it, shuffled off its mortal coil, dead, kaput indeed

Lift the reservoir to access it from below. The wires are short , so don't lift it too much

Post by **oragex** » 14 Sep 2017, 06:15

The sensor gets busted when the reservoir is lifted without unplugging the sensor. Try first see if the float inside the sensor doesn't stick, then replace the sensor. Don't forget to unplug it all times when working on the reservoir

SnowOwl · Post by **SnowOwl** » 14 Sep 2017, 21:40

Thank you abscate and oragex. Before I got your reply, i lifted the reservoir looking for the sender, There were two wires going into the bottom of the reservoir and I jiggled them some. I couldn't identify the float, and I don't know if it is high, low, stuck or whatever. I couldn't get the connector apart because I couldn't get my hand in there. If I really had to separate the connector I'd probably have to remove the bar that holds the top motor mount. Might be an opportunity because I think the top motor mount is bad again anyway. It has been replaced threes times at the dealer over the years. Anyway, I didn't really accomplish anything but I don't think I broke anything either. When I started the car back up, the message was gone, but about the third time I started it the message came back and stayed with me all day. I'm guessing something was temporarily helped by my jiggling, a better connection or something. Assuming I could get the connector apart, how would I take the sensor out to replace it?

Post by **abscate** » 15 Sep 2017, 05:26

It just slides out if I recall . It's magnetic, so no coolant is released when you remove it.

I think my Abby debuted in MVS replacing it in a thread here

viewtopic.php?f=1&t=57659&p=292541#p292541

SnowOwl · Post by **SnowOwl** » 17 Sep 2017, 08:06

Thanks abscise-

Once again, just plunging ahead without waiting for good advice I went looking for the float, and poked a screwdriver or something down in the reservoir until I felt something jiggle. Now the message is off for a whole day. I'll see how it goes.

SnowOwl · Post by **SnowOwl** » 17 Sep 2017, 08:08

Abscate, not Abscise. I have no idea why spell check wants to correct your screen name. Thank you.

Post by **abscate** » 17 Sep 2017, 18:32

Usually it corrects to abcess.....