Voltage regulator black wire

[cfm65@me.com]

Hi Guys,
Could someone please let me know where this black wire originates? This end is dead, no + no -.
Much appreciated.
Regards
Chris

[BobH]

Hello Chris, the black wire connects to terminal DF on the alternator, i think you'll only see a voltage there when the engine is running

[lpeterssen]

Dear Chris

Bob is right, none of those cables will show anything unless the alternator is operating.  You have one brown , cable connected to “D-“ which is a ground one terminal with two cables one blue and the other red/blue which are connected to terminal “D+”  and run your charge light at the instrument cluster. And finally the black cable you mention which goes in between join8ng terminals labeled “DF” at voltage regulator and alternator.

Best regards
L.peterssen

[cfm65@me.com]

Apologies guys,
This is the voltage regulator on my E Type and it was supposed to be posted on the Jag forum.

The wires are brown/purple, black, brown/green.

Thanks, I’ll give it a go.
Much appreciated.
Regards
Chris

[BobH]

Ah, totally different, looks like the black is an earth/ground, see if you can trace it and see if it's a bad connection somewhere

Perhaps this post should be moved to other cars in case it causes confusion