The small diameter brown wire from the alternator to the starter solenoid has been disconnected. The wiring diagram shows the large diameter brown wire going to the same point on the solenoid. The ignition warning lamp goes out when the engine speeds up and the battery charges. I do not understand why 2 wires run from the alternator to what seems to be the same point on the solenoid. Can someone enlighten a poor dumb civil engineer?
this maybe to excite the diodes.
In the Workshop manual the two brown leads from the starter soleniod connect to separate alternator connections marked '+' and '+ BATT'. (A third connection at the alternator is marked 'IND' and a Brown/Yellow wire connects from there to the ignnition warning lamp.) Possibly your alternator has been replaced at some time and the '+' and '+ BATT' are separated off internally so that only one connection is required between the starter solenoid and the alternator. (If it ain't broke, don't fix it!)
Peter C. (Daily transport 1974 MGB for past 25 years)
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