Going to look at a R53 that was reported to be running fine then driver reported a burning electrical smell and car quit running. Has around 140K miles on it. I've read many threads about the battery at end of life causing issues and wiring harness chafing on the earlier cars. Any known issues on the last year R53 that would be a good place to start the checks to find the problem?

 

That could be the smell of burning rubber = separated / grenaded crankshaft pulley / harmonic balancer / dampener. When mine went recently I got this smell very strongly. Car ran for a time okay but eventually went into limp home mode.