95 alternator exciter wire (engine swap)

[BillB]

95 yj 2.5l manual trans - Recently swapped in a VW 1.9 TDI ALH engine with standalone ECU and harness. Starts and drives good. Need to connect the Jeep alternator exciter wire into the new standalone wire harness to get the alternator to charge. 2 wires that went to the jeep alternator: dark green (Field Generator Driver wire) and dark green with orange stripe (Field Generator Source wire). Assuming the dark green wire (no stripe) is the exciter wire? When i turn on the key or start the engine hoped to see 5 volts from the dark green wire. Neither wire outputting any volts? Getting 12.4 volts at the battery and 12.3 volts at alternator. Hoping someone on the forum can help me out. Newbie, never pulled or swapped an engine. Owned my Jeep since 95 and always done all the maintenance and parts replacement. Thank you!

 

[BillB]

Found great and simple solution in the TDIclub forums. Patch a 12v light and socket (used side maker socket and 1W led blub) to a ignition on source. In my case added 12V fuse pigtail to ignition on fuse. Connected it to one of the socket wires. Connected the other wire to the new alternator exciter wire. When I turn on the key, the light blub goes on. Once the engine starts and the alternator starts generating electricity on its own the alternator's output will equal the ignition switch voltage and the bulb will go out. Recommend reading the complete TDIclub posting. Posted this with the hope it helps someone else out. The folks on the TDIclub forums respond fast with good solutions.

https://forums.tdiclub.com/index.php?threads/alternator-wiring.356457/#post-3850134