Enter the following cheats at the Code Entry screen in the Secrets option section. The following codes need a master or bonus code which will only work on certain discs. You may have to try more than one.
Bonus Code 76538
Group B Mode and Cars: RTNITJ
Bonus Code 34674
All Bonus Cars: ZCNGMW
Expert Mode: IRZQNT
Mirror Tracks: FEQRJV
All Tracks: HCHSFD
Bonus Code ?
All Weather: CLRWTR
Group B Mode and Cars: CFCKGL or YFHPGW
All Bonus Cars: AIDLAU
All Tracks: BSDJUC
Expert Mode: HIQNRM
All Parts: FUDWHC
All Tests: DMLPOD
Mirror Tracks: EPDZJF
Unlockable Bonuses:
Come in first or second in the championship listed to unlock the car or cheat
Bonus - Championship
All Tests - Group B
Audi Quattro - Group B
Citroen 2CV - 2WD (Normal)
Expert Championship - 4WD (Advanced)
Extreme Damage - 4WD (Advanced)
Ford RS200 - 4WD (Advanced)
Ford Transit Rally Van - 4WD (Advanced)
Lancia 037 - 2WD (Advanced)
Mirror Mode - Group B
Mitsubishi Pajero - 2WD (Advanced)
Peugeot 206 - 4WD (Normal)
VW Golf - 2WD (Normal)