FMGC says VOR/DME ABC is located bearing 150°/20 nm but raw data are 165°/21nm. according to FCOM a check is valid if distance difference is less than 3 nm but doesn't say anything about difference in bearing. the above test is then valid or not ? (15° of bearing diff & 1 nm of distance diff)
The accuracy check is done both on distance and bearing:
1. DISTANCE: compare NAVAID distance with FM distance on ND or check with FM PROG page: error shall be less than or equal to 3 NM (1 NM on approach).
2. BEARING: Check that the needle (raw data)
overlies the corresponding blue navaid symbol (FM computed).
Hope that helps,
fredgrav