ADU5789MS Fitting electronic dizzy to A+ ballast type ignition.

998cc 1982 to 1993
From 1982( X reg ) 998cc minis were fitted with a ballasted ignition
system. From 1990 1275cc carburettor minis ( RSP and mainstream Coopers )
did not use this system. Ballasted ignition means that the coil is supplied
with 9volts during normal running, but is supplied with 12 volts when the
starter is operating. The ballast is fitted by means of a resistive wire
(pink with white tracer) and can normally be seen at the positive terminal
of the coil. When fitting an electronic distributor the power supply will
need to 12volts. The module will not run correctly with 9volts. Therefore a
new 12volt supply wire will need to be fitted between the fusebox and the
red wire on the distributor. Be sure that the new 12volt supply is not fused
and ONLY available when the ignition switch is on.
Alternativey, fitting our sports coil will provide your mini with a better
spark and performance. To fit MSC105 sports coil to a model that had a
ballast system you must change the resistor wiring to the coil. The two
wires joined together by the terminal attached to the positive side of the
coil which are white and pink and white and yellow. You need to disconnect
them and tape them up securely to terminate them. To replace this
old wire run a new wire from the top left terminal of the 4 fusebox where
there is a large white cable, down to the positive side of the coil. This is
now live when the ignition is turned on.