Battery and cables

Positive Earth Electrical Systems
All models prior to the introduction of the Mini MkIII in 1969, whether a dynamo or an AC type alternator was fitted,  had positive earth electrical systems. The only exception to this rule was models fitted with the optional ACR type alternator.

From 1969 on (i.e. MkIII onwards), all models were wired for negative earth.  Once again, there was a small exception to the rule - the first few hundred 'MkIII' Vans and Pick Ups retained the earlier positive earth system.