Hello Gurus can you please explain to me the path of the B/LG wire of the MAP sensor?




does B/LG split to X-05 and (14) on the schematic?
if so, would it mean (14) flows to the connector at X-12?
if so, B/LG should have connectivity along the igniter wires LG/W, LG/R, LG/B?
and also would B/LG have continuity at 1J (BR/B), 1G (BR), 1H (LG), 1T (L/B)?

 

This might be helpful: RX-7 Wiring Help
I'm doing Emission harness repair and ecu re-wiring and have made that resource to accommodate myself.

Yes.

No.
B/LG wire has a continuity with 4D (BR/B). And it also has a continuity with the SHIELD wire for ignition module.

 

Your wire B/LG, is a ground AND also provides connectivity for shields to achieve ground.

The FD daisy chains lots of grounds. LOTS. It 1) saves the amount of wire needing to be run, 2) provides plenty of places to tap for shield wires. Shields are important. They're on your wheel speed sensors, Igniter, and Bose speaker lines to minimize interference which would other wise effect the signals traveling (as most other connections are just a constant voltage source).

As the diagram shows, this ground is running across 3 separate harnesses. Emission, Front, and Engine. aka everything inside the engine bay. It's a lot. Remember a lot of this stuff was made because it was the early 90s and they needed vacuum and igniters to run everything, on top of minimizing cost at the expense of long, convoluted wire runs.

It can be simplified....a lot, but that requires redoing entire harnesses. Big project, but major simplification is possible.

 

correct, its a daisy/pass through