Greenmantreeherder

Hi, I've got a problem with my 2003 Citreon C5. The Right Indicatoronly flashes four times when selected if the sidelights are off. It flashes perfectly with side lights on. The horn don't work with the lights off but works fine with the lights on. The problem seems to be with the Com2000 unit (indicator, radio, wiper assembly) but on eBay I see several with different part numbers. Does anyone have the part number for a Citreon C5 VTR HDI 110 2.0 Litre Estate Com2000 please? I been told a BSI reset might do the trick. I've found the procedure. I've looked on the internet and I can get a Drivers manual and I can buy a workshop manual but no parts catalogues. Thanks Paul