Most problems in life, I find, usually have logical solutions... except Italian auto-electrics! Not being an auto-electrician I can't make much sense of this so let's see if any of you guys can...
The wires
to the black block connector are as follows: red, black, blue/black, brown, green/black as stated by lanciamad. Both brown and black are live. The wires
from the connector
to the ignition switch are as follows: red, blue/black, brown, black. The first thing that's obvious is five wires have become four... the black wire, which is live, connects to nothing! There is no wire in the block connector on the switch side to connnect to it. The next obvious thing is that the green/black wire has changed to black... I'm sure the Lancia technicians had a reason for doing that but... Anyway, all the wiring looks original.
When I put my multimeter, set to continuity, onto the connections on the
switch side without it connected to the other side I find that it appears to work as it should: On turning the key the brown wire connects to the black wire (to connect the ignition) and also to the blue/black wire (to give power to the wipers/lights etc). Turning the key to the starter position means the brown wire also connects to the red wire, which would activate the starter. So all appears well with the switch. But connected up all is dead. The 12 volts that I saw when I put the meter onto the brown wire does not appear at the other wires when the block connector is connected up- and the brown wire itself instantly reads no volts, and doesn't connect to the other wires when the key is turned,
despite those wires proving ok in the continuity test.
If I put a jumper wire from the brown wire to the blue/black ignition wire I get nothing- no ignition lights, whether the connector block is joined or not.
Despite the fact that the brown wire reads 12 volts when not connected.
Now, back to the live black wire that goes nowhere. If I put a jumper wire from the black to the blue/black ignition wire I get ignition lights. Connect the block together and then I get full operation of everything. Turning the key operates the starter too. What is the black wire for if it is not connected to anything? Bear in mind it appears to carry enough current to power the ignition and all it's extras- starter motor, lights, wipers, heater fan etc etc. I know because I switched them all on at the same time. The battery connections are fine and the alternator is functioning correctly- battery is being charged.
Any of this make any sense?
Is it safe to run the car using power from the black wire?
Where do the black wire and brown wire originate from- can I trace them to their source or are they likely to be pink and yellow at the other end...?
As the switch and switch wiring appears to function correctly when continuity tested I'm very confused with this.
As soon as the block connector is joined the brown wire's 12 volts becomes zero, and those 12 volts won't power the ignition when connected with a jumper wire
without the block connected; so if the problem is a short circuited switch it doesn't explain that. Nor does it explain correct functioning on the continuity test of the switch. Or does it...? If any of you electrically minded folks want to tell me how daft I am because it's totally obvious what is happening then please chip in- I don't mind if I look like a numpty... it's all a learning process!
Andrew.