850 How to read an electrical diagram

[manovlov]

Hy Guys,

I need someone knowledge to understand how to read an electrical diagram.

What these numbers mean circled in red ( 4 3 2) ?
Why use "double point" on the ones below (24/2:2) ?

Thanks to those who will teach me.

Schéma electrique 850 - copie.jpeg (512.67 KiB) Viewed 1446 times

[abscate]

Every item in the electrical system has a code number which is formatted with two numbers

XX/YY

The x number tells you what kind of item it is like a switch, relay, fuse, sensor, etc.

The YY IS the actual number, so in your example of 24/2:29…..

1.24 tells you it is one of the huge under dash connectors in bright colours
2 tells you it’s the second one
The 29 is referring you to the pin for the electrical connector

So it’s pin 29 in connector 24/2

2 The other one..it’s logic module as it starts with 4 ( note your ECU is also a 4/x number)

4/48 will have a connector on it. And if you pull that connector off the pins are number 1-8. Those numbers are what the diagram refers to.

1/1 is the battery
2…are relays
4 are electronic modules

11 are fuses…..you will see 11/5 to denote fuse 5 in fuse box 11
24 are connectors, there are many of these 24/1, 24/2 …..


The very large modules sometimes have connectors with an a A and B side. The ECU does this. Those pins are labeled A:1, A:2…….

[manovlov]

Wow. More clear, it's impossible. Merci mon ami !

Apparently, the starter "icon" seems to be this one :

starter .jpg (6.93 KiB) Viewed 1431 times

Could you locate the "starter on this diagram abscate ?

Manov

[abscate]

This is one of those things that makes these diagrams a bit more difficult. In the old days, wiring was so simple , everything fit on one page.

Locate the ignition switch, 3/1. The circuit thst connects 12 volts to the small wire on the starter motor is always terminal 50 in EU ( that’s a standard, like terminal 15 is switched 12volt , terminal 30 is always 12v from battery)

You will find no connection to terminal 50 in your diagram, because this circuit is covered on another diagram, probably called primary power or something like this. It will have the starting and charging circuits on it

Look next to the ignition switch for the little table. That tells you what pins are connected as you rotate the key into each position, fun to play with on a rainy day with a good glass of Domaine Giachino

[manovlov]

Ok. Thanks so much abscate. It's more "easy" to me .

I don't drink wine, it clouds my judgment... On the other hand, a single malt...