I'm not sure I'm following all your steps - replaced bad Mk3 with Mk4, but then did you attempt to load the software to update the system, before attempting to read a nav disc??? I don't know if the Mk3 CDs will work in a Mk4 DVD. You may need to get the DVD version of you area.

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Mark _______________________________
2001 X5 4.4i topaz blue/sand Sport, complete Dinan S2 , hitch, V1, tint, BSW Stage 1, Alpine INA-W910BT
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