| I had a very similiar problem after picking up my 900SL the first outing to Brands last year kept cutting out couldnt find the cause by the side of the road and limped home after moving battery terminals.
sent back to dealer i got it from and it turned out to be a broken positive lead about 4 inches from the battery inside the thick protective plastic only cut out over bumps etc so was parting the wires.
a new positive lead cured it.
ian |