Reading wiring diagrams, the finer points
 

I understand the basics of electricity and reading wiring diagrams. The diagrams in my Bentley manual routinely include notations I don't know. Can anyone tell me what the following mean:

NCA= ? No color assigned??
J/C =
J/C (red tape)
J/C (78)

A number where a line connects to a component, is this a terminal number? Or wire diameter?

A termination dot has an arrow pointing out of it that doesn't point to anything else?

Thanks
Nathan

Specific example.........
 

Nathan,

Could you to be more specific and indicate what page/s you have in mind? I could look into the Carrera Bentley manual and compare it to the factory wiring diagrams if this would help you.

Tony

the factory manuals normally have a code page preceeding the diagram pages.

Factory Shop Manual........
 

John,

The guy is using the Bentley Carrera manual and not the factory shop manuals. From his post, the numbers seem to be the terminal numbers indicated in the Bentley wiring diagrams.

To make certain that we are reading the same page of the manual, I requested for a specific page and example. Otherwise we will be all guessing.

Tony

The number is typically the pin number of the mating connector.
For the dot with an arrow, is that a ground connection. Are the wires brown?

Could you give some page numbers where the other nomenclature is?

Tony, here's one.

I'm most curious about " J/C 4 PoleLV and the symbol it's next to...http://forums.pelicanparts.com/uploa...1394650755.jpg
http://forums.pelicanparts.com/uploa...1394652642.jpg

Four-wire branch connector........
 

Nathan,

I used the '89 factory wiring diagram for fuse #2 (luggage compartment) and here are what I found out. Fuse #2 goes to a 4-wire branch or connector. One goes to A/C relay @terminal #30, operating relay @terminal #30, and to another relay (?).

Dennis (Timmy2) might be able to interpret the symbol (J/C-4 pole-LV) for you. Wish I could tell you more. Good luck.

Tony

Could be junction connector 4 poles insulated connectors ?
The arrow with no number or simbol could be that there is nothing connected to that terminal.

I'm with donporfi, in the older Bentley BMW manuals like E36 etc. they have the same style of connection point graphic but they call them junction points, J/C is probably a junction point connector and 4 pole means it will have 4 positions although only 3 will be used. Since it is passing + voltage then it would be insulated. The LV part could be a location in the car. Usually they have a section at the very beginning of the electrical section with locations of each component and junction point.

Thanks guys.

Electrical diagrams are one area where the factory manuals are far superior to anything else available, at least through the SC.

+1,
I never look at the Bentley for wiring information.


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