You indicated you get ~19 volts across the voltage regulator (A1) terminals 5 & 6 when flashing (S1 in START engine running).
If so the reading of 19 volts is way too high. It ought to be ~7.6 volts.
Since the DC voltage you are reading at A1 across 5 & 6 is so high it tells me there is likely a problem with the wiring from there to the Field Winding in the gen head or an issue with the field winding itself.
The field winding resistance should be 10.54 ohms to 14.26 ohms or about 12.4 ohms on average.
With the set
OFF disconnect the wires to A1 5 & 6. Using your meter measure the resistance between the wires removed from terminals 5 & 6.
You should read about 12.4 ohms (the resistance of the field winding).
Reconnect the 2 leads to A1.
If you din't measure about 12.4 ohms in the test above then remove P5 from J5 and measure the resistance between pins 1 & 2 in P5.
You'll need to turn the locking collar on P5 before you can remove it.
It should be about 12.4 ohms. If you measure something way different then there is a problem in the wiring from P5 to the field winding or the field winding itself.
While you have P5 unplugged clean the 4 contacts in P5 and the 4 contacts in J5 and then plug P5 back in and turn the locking collar to secure it.
After cleaning P5/J5 and reconnecting them start the set and see if the voltage across A1 terminals 5 & 6 is still about 19 volts DC or closer to 7.6 volts DC when flashing. (S1 in START and engine running). Also see if you get ~ 120 volts AC at the convenience outlet when flashing.
Here is a schematic of the flashing circuit...
![Filed Flash Schematic 802 803 3-10-21.JPG Filed Flash Schematic 802 803 3-10-21.JPG](https://www.steelsoldiers.com/data/attachments/583/583208-bfa4d24fdc3e025915a12832b79c2ff5.jpg)