Does anyone know which wire running to the PCM supplies the power to it? Please let me know if you do.

 

I am working from the maintenance manual for the 99. Probably not correct from the publisher.
Says start- run A21 feeds Junction Block
Fuse 11 10A Pins #18 and 17 and Fuse 9 10A Pin # 14 and 13
Comes out 20 LG/BK
Splits @ S171 Feeds ECM 18 LG/BK and PCM 18 LG/BK
PCM pin 2 C1 Fused ignition switch output (st-run)
Hope this helps if not shall try to provide you with more info.

 

Thanks man for the help. I should be able to decipher it.