Hi Dave, dont know why "Bp codes" are so difficult I have at best a 75% success rate I have another "bp" calculator but that is based on a ten digit serial no but that can give up to seven codes but I have no instructions as to how to work out the correct code it gives me bp1, bp2,C1,C2,bmw,ren,c_old and each comes out with a different code for the same ten digit serial no!
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