yet another alternator question

[DanTribe]

I've moved my Yanmar control panel which involved unplugging and re-plugging the wiring loom.
Now the ignition warning light does not come on [I've checked the bulb, that's OK], so I've obviously mucked summat up.
How do I test to find out why a light doesn't come on when it should when the charging stops? [And how does the light go out when there is electricity?]
I have an Aardvark battery management and the light for that doesn't work either.
'tis a mystery, this electrickery.

 

[sailorman]

I've moved my Yanmar control panel which involved unplugging and re-plugging the wiring loom.
Now the ignition warning light does not come on [I've checked the bulb, that's OK], so I've obviously mucked summat up.
How do I test to find out why a light doesn't come on when it should when the charging stops? [And how does the light go out when there is electricity?]
I have an Aardvark battery management and the light for that doesn't work either.
'tis a mystery, this electrickery.

the light comes on with the key turned & the + is livened up, it get the - from the alternator.
when there is output from the alternator down what was the - wire the voltage equalizes & the bulb goes out