Failed backlight Agilent U1252B

[Lorenzo_1]

Back light on my Agilent U1252B no longer turns on. It's only a year or so old. Everything appears to work OK. Played with Menu options to change backlight timer and also Reset to factory defaults. Also removed/reinstalled batteries after power on with no battery installed (presumed this would drain any reserve charge in caps). No effect. Simply beeps when I press backlight button.  Has anyone encountered this?  Is it a known problem or is there another fix I might be missing? It's under warranty but a nuisance to ship back and be without.