I just changed my regulator... Here's what I did...
Battery was flat and not charging:
1. Charged the battery on the Optimate
2. Tested the battery terminals - they were tight
3. Put the voltmeter across the battery - it measured 12.62V DC
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_D3A2A275-3486-471A-A9C5-42DDDDC5B292_zpscbcsaygs.jpg)
4. Started the engine
5. Put the voltmeter across the battery - it measured 11.8V DC
6. Split the 77 connector
7. Put the voltmeter across the battery side - it measured 11.8V DC
8. Put the voltmeter across the regulator side - it measured 3.2V DC
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_B0C4A8E3-D400-44DB-9769-AFBEA5B4050E_zpsdahlegig.jpg)
9. Split the stator outlet connector
10. Put the voltmeter across each pin to each pin (each winding) - it measured 15.6V AC on each
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_361652A9-3E71-408D-85D5-B60DE42900B5_zps2sjduqro.jpg)
11. Shut down the engine
12. Measured resistance across each winding - it measured 0.4 Ohms on each
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_BA4B14D5-0FDA-4EF8-9ECB-AD807D421DAC_zps05esmuw5.jpg)
13. Measured the resistance of each pin to ground - it was Open Loop on each
14. Replaced the regulator
15. Tested again - 12.49V not running and 13.87V running
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_8CB5555D-C2F5-47AD-BA49-624864E8DD15_zpsqdomyz6r.jpg)
As I was replacing the regulator, I:
i. Copaslipped the screws holding the regulator on
ii. Put liberal amounts of silicon grease inside the 77 connector - a known weakpoint
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_ACF29B08-5E48-4116-87AF-4F44EABD3630_zpsh66ce3j0.jpg)
Then, just like a grandfather, I stripped the old regulator of anything that may come in use another day...
![Image](http://i219.photobucket.com/albums/cc266/pashlipope/th_2018CB89-A646-49AA-B039-CC9077F7BADB_zpsnf0t6k1s.jpg)
I made a little troubleshooting flowchart too...