Interpreting FSM wiring diagrams

[EricE]

I was looking over the FSM wiring diagrams over the weekend. Specifically the two pages of wiring devoted to the connections into the ECU. I spent at least a couple of hrs at it but was not able to make heads or tails of it.

For instance. The ECU shows wires coming into it and labels those connections. Specifically I was trying to find the wires into the ECU for the O2 sensors. One was labeled E2 (I actually forget the exact number but it is not important). To me that would mean I should look for plug E and wire pin 2 on the plug. But there were only 4 plugs coming into the ECU and they were labeled A,B,C,D. That means that there was no plug E. Whats going on here. The diagram actually showed plugs on up to G going into the ECU. Can anyone explain what the E,F, and G were?

Another case showed me that my belief that those were plug indicators was totally wrong. Plug D had pins up to #22 but the wiring diagram showed a wire into D25. Huh? (I said)

 

[Cruiser804]

Not being a smart ass here but have you read the "how to use this manual" section.

I don't know the answer to your specific question but the legend in this section tells you what all the numbers stand for as well and how to read the plug number and the color codes for the wires.

I down loaded this from toyota techdoc.com

 

[dfmorse]

It takes a lot of study to figure out the format system the Toy people have applied to their diagrams. It (the format) does not conform to WECO (Western Electric Co. ) systems layout, but its close. More reading of section "B" is necessary. Don't get discouraged. I've spent days doing the same and still don't know what I'm doing.

...

 

[billstoyshop]

E2 is the ground. I will check tomorrow and help you out on your query. Bill-----What are you trying to fix?

 

[EricE]

I studied the key to the wiring diagrams very carefully and it did not resolve my question. Perhaps I missed a key. I'll look for this "section B" and see if it is the one I studied.

Specifically I was trying to find the pins (in the ECU plugs) that link to the O2 data wires. One is called OX1 and one is called OX2. I wanted to be able to test continuity between the ECU plugs and the O2 plugs. To do that I needed to know exactly which pins those were.
Note that I have solved my problem with the O2s so this is just an academic exercise so I’ll be able to understand the wiring diagrams next time I need to. I solved my problem by testing continuity between the O2 plugs and the check block in the engine compartment.