Bought a used 2006 S60 2.5T about 1.5 years ago.
I got the "coolant level low" warning, and looked at the reservoir, and it's empty. Looks like maybe there's a bit of yellow/green in a crease in the reservoir. Didn't look inside the radiator, yet. The problem is I have no idea what kind of coolant is in there. I know you can tell by color if it's propylene or ethylene glycol. I read there's also a 3rd type, that you cannot mix with regular antifreeze, or it will turn to goo and kill your engine. Finally, I found there is "Genuine Volvo" antifreeze, and I can't find out what's in it, nor if it's a special color.

Not sure how to proceed. I'm thinking I'll know more when I remove the radiator cap, but if the level is low enough, I may not get to see what color the coolant is. (and obviously, I'd have a bigger problem...)

We're having cold weather, so I'm not afraid to drive the car maybe a mile, while it's cold, but more than that I suspect is not a good idea.

How best to proceed? (Towing to a repair place is last on the list...) I'm handy, but I'm not a repair person.

 

first problem is to figure out where the coolant went. Look for leaks on the sides of the radiator, around the hoses and under the reservoir. If you smell a sweet smell in the cabin when the heat first comes on, you should check for a leak around the heater core. Once you fix that you should do a deionized/distilled water flush and refill with silicate free antifreeze (aka green coolant) - avoid mixing with replacing with an OAT coolant (ie Dexcool) which is orange. Over time even the green coolant will pick up some brown from the engine, which suggests a good time for a flush.

 

Hi,
To err on the side of "do no harm", since I didn't know what's in there, I used distilled water, figuring it would only dilute existing antifreeze a bit. Just added it to the reservoir, didn't take but maybe 10 oz. The "Coolant Level Low" light did not come on when I started the car, and after it idled long enough for the temp to come up, I checked the reservoir. The color was green, so I believe that Genuine Volvo antifreeze was, indeed, in there.

I'll be taking the car in for maintenance next week, I'll have them test the anti-freeze, maybe pressure test, and also I'll be watching the level like a hawk. And, I'll get a bottle of the Genuine Volvo 50/50 antifreeze, to have on-hand, just in case.

Now I at least know that the entire radiator was not empty, which was my greatest fear. The car won't be taken out on any long trips until I get it into the mechanic.

 

any "green" 50/50 mix will work or you can drop in a similar amount of unmixed. You can also get a quick specific gravity test to estimate where the coolant's mix is to estimate the freeze temperature.

 

Bright green coolant is not Volvo coolant. Volvo coolant is one of two colors.
Blue (looks just like washer fluid) or it's dull green in color. Anything else is generic coolant and not recommended for your car.