DRB III failing to communicate with PCM.

What I've learned so far:
  • K-line logic Hi/Lo is Vbat/0
  • K-line Measures Vbat w/DLC breakout box and NO scan tool connected.
  • L-line Measures 5v w/box & NO scan tool
  • Some communication must be initiated to see K-line logic stream - a connected scan tool can do this.


Have found no English postings about L-line - a few Spanish ones but nothing in English.

QUESTIONS:

Is L-line used?
IF YES:
  • What is Vhi/Vlo?
  • Is it a different data stream or a "mirror" of K-line?
  • IF DIFFERENT: must communication be initiated to see logic stream?


I did notice that my battery was 11.3v and K-line was also 11.3v: If K-line is supposed to be 12v Hi and I only have 11.3v, could this be why my DRBIII is not initiating communcations? (But then it doesn't with engine running either.)

NOTE: After days of "The PCM is not supporting Scan Tool Communications" I got my BOB (Break Out Box) and found it extremely tight to connect. I then connected my DRB to the BOB and actually got to the "ENGINE" module selection which then failed to communicate. All subsequent connects failed with the "The PCM is not..."