Volvo V-40 computer problems

I made a mistake and bought my 2000 volvo from a dealer without taking it to a mechanic to check it first. When I test drove it everything seemed perfect and the car looked in a great shape. A few month later I began to have problems, the car already died three times on me, the last time I changed the battery wires, later their was a problem with the key hole. I already spent 1200 on it and now the mechanic tells me that I may need a new computer software so that my car does not stop again, which would cost another thousand dollars. Has anyone else had these many problems with volvos? Is computer reset necessary or mechanics are trying to get more money from me?

Ask the mechanic to list the stored computer codes and post them on this site.
It’s unlikely that your problems are a result of the computer software.

Don’t know about your computer issue in particular. Generally Volvo’s are very expensive to repair. Your experience is not unique. My '98 Volvo seemed to need one to two repairs a year at over $1,000 per occurance. Welcome to the world of expensive repair bills on older Volvo’s. I sold mine. It costs me less per year to maintain 3 cars than it did for one Volvo.

I doubt the trouble is due to an intermittent problem with the ECU. If there are any fault codes generated when the trouble happens it would help us to know what they are.

Problems like this are usually due to simple faults like bad electrical connections. Possibly with a relay contact or in the ignition switch. Problems in those areas may not generate any error codes. While the fixes for these troubles are usually simple and not very expensive it can involve a lot of time in searching for the trouble if it is intermittent. Tapping on suspected trouble areas can help find the trouble source at times. I like to use a screwdriver handle to tap with.