Ok, so the car overheated unexpectedly, steam came out from undeneath the glove box, and the dashboard started lighting up like a Christmas Tree. After letting the car cool down, replacing the coolant, the car started up again and ra fine for about 2 weeks...no coolant loss.

All of a sudden , it happens out of the blue, except this time the windows rolled down, car would not start, no, not even turn over and got a key error code.
After doing abunch of research online, decided it was the ECM (Electronic control module) . Removed it from underneath dashboad (major pain) cleaned it up,let it set and reinstalled it. Same key error. I replaced the battery as well.

At any rate, after calling a couple of locksmiths, it was determined dealer could only reprogram the key key . Had to have the car towed in.

Come to find out, the ECM was shot, becaus the steam that we saw underneath the glove box was from the heater core malfunctioning in a way that held the coolant I put in, but ultimately failed again.

Had to replace the heater core, ECM and also got the timing belt replaced. $3,800 was total bill, but all has Lifetime Warranty from Volvo and car only has 115,000 miles and car was given to us by a family member who bought the car new in 2005, so I still consider it a win.

Volvo did not replace a factory hose assembly that connects to the heater core. There is a pair of hoses with a connector. One of the connectors failed. I was able to repiar it and it has been fine for the past 2 months. Volvo dealer said, "that hose assembly never fails, so we did not suggest to replace it". I think they did i on purpose and knew it would fail, but maybe even rigged the connectro to do so. The car is 14 years old, that particular hose assembly never failed, and only does after Volvo replaces all that stuff?

Went all the way to the top. They would not replace the hose assembly, unless I paid $400. Being a shadetree mechanic, when you replace anything with a heater, radiator etc, you replace the hoses. They should have told us and suggested it to us. I would have spent the $400 when everything else was getting done.

Good news car runs great, had a new alternator installed prior to us taking the car, and most major components have been replaced, and we are hoping to get 200,000 miles out of the car.

We love the car. Bad news is Volvo dealership was disaapointing to say the least. I suggest NEVER to use one if you can get the work done anywhere else.

PS. The hose connectrors I am talking about are dead center, on top easy to see, in back closest to engine compartment. There are 2 hoses side by side. That is the one that failed.