My 2002 Volvo S60 was in a car accident. My

I would replace the radiator. The radiator has plastic end caps and and they will leak sometimes where they seal with the metal core of the radiator.

Check the fuel lines they run from that side of the car to the front

it a round cap with 2 bolt should be on the end of the camshaft

I had this problem on my 02 s60 after messing with the battery. The problem is that the computer is stupid and "forgets" how to manage the car if it completely loses power.

To retrain it you basically just drive the car. I've seen several sets of instructions but here's what works for me:

1. Start the car and let it idle until warmed up.
2. Using moderate throttle (don't floor it) get the car up to highway speeds.
3. Slow down to a complete stop.
4. Repeat 2-3 a few times if you're so inclined.
5. Done!

Skipping the highway part will work too, however, I've heard it can take much longer to retrain the computer (weeks to months depending on driving habits.)

On this website, you find fuse box diagram and description for Volvo S60 (2002)

Volvo S60 mk1 First Generation 2002 fuse box diagram Auto Genius

if it sounds like a clicking noise, it could be the rear sway bar links. or the rear exhaust bracket. both common problems with volvos

the battery is located in the trunk underneath the floor. there should be a handle on the floor and you lift it up to get to the battery. there is a positive battery cable post under the hood near the driver side strut mount, next to the fuse box.

Probably its linkage mechanism is dirty, stuck with grit, and needing a lubricant.
Spray some light lubricant, such as WD-40 on the trunk lock. Then use a flat-end screw driver to try to pry the lock back-and-forth. This should free the linkage mechanisms in there and allow the lock to operate.

It more than likely may be the fuel pump. My girlfriend recently had the same problem with her S60 I came across a recall for the fuel pump. I took it by the dealers and they took care of it free of charge. The only negative thing I guess is that they kept it for a few days. 

the battery is in the trunk..should be straight forward R & R for husband ...good luck