ground problem? (1 Viewer)

[jblueridge]

I a beginning to think my electrical problems are related to a bad ground wire or situation. I don't think two separate relays would go bad and Buzz at the same time.

1) There is a ground from the starter to the frame: it is like 0 or 00 size.
2) There is the factory ground from the negative battery terminal clamp down to the engine.
3) From that same battery terminal clamp, there is a modest wire from clamp to body/inner fender.
You can see numbers 2 & 3 in this Toyota diagram... part # 28800B.
Any others I should know about? Maybe I should add some?

 

[jblueridge]

I re-tested most everything again today.
Batteries are charged.
All fuses in the fuse box are good.
Fusible links good (zero resistance).
All the relays check out as good.
When horn or headlights are turned on, its relay buzzes as if not getting enough power.
Starter switch tests out as good except for the START position. On the starter switch connector I am not getting continuity between pins 3 & 6 or 3 & 4.
Below is the diagram from the online FSM. I have been using the lowest picture as my guide.
Maybe the 2nd picture is correct? Maybe there is another diagram somewhere for 13BT w/out glow plugs.