In case it helps anyone, my 2007 xc90 D5 went into limp mode with messages: urgent service required and anti-skid malfunction. Engine was also feeling rough. Vida threw several codes including 'injector 5 signal missing' and 'glow plug relay'. All I did to remedy was remove the electrical plug on injector 5, spray with contact cleaner, and then reasemble. 10 min job, and she's as good as new.