1GGZE wiring help

[ztd]

I'm wiring my 1GGZE into my RA28. Currently I'm setting up a fuse box for the engine and re-doing the wiring to the ECU as it was poorly done before.

I'm following the 1GGTE wiring as closely as I can, but things like fuse ratings, supercharger wiring etc are missing. I've also had to make up a Circuit Opening Relay as that was missing completely (fuel pump was wired direct to ignition).

Here is my wiring diagram so far - apologies for the quality, I scanned my drawn one: http://imgur.com/a/n5MC1 (Sorry I can't embed, I couldn't get the image upload to work and it doesn't seem to embed images here either).

Some things I'm not sure about:

1. Is my fuse setup right? One large fuse between the alternator +14.4v output and the rest of the loads?
2. How do I size the fuses? I've looked for current draw and found them for some loads (e.g. 10A for my fuel pump) but what if I can't find that info online anywhere?
3. Is my proposed alternator wiring correct?
4. The previous setup earthed everything in the fuse box to E1 at the ECU. The wire was melted and bubbled! I've drawn in a 'master earth' which I was thinking could do the same, all relay earths join there, but instead of going to ECU it would be a thick cable out of the fusebox screwed to the chassis. Is this OK? Do I need more elsewhere?
5. Is it a good idea to buy relays with diodes built in if they're the same price as non-diode ones? Will I have any situations where these won't work?

Thanks!

[wilbo666]

1) I didn't see the connection from the alternator to the battery...the fuse is there, but I didn't see the connection to the battery!

2) Fuses are usually sized to protect the wires. Do you have the 1GGZE wiring diagram with fuses sized? If not I'd probably look to use the 1GGTE fuse sizes.

Also you don't need a separate fuse for the two COR relays, you can just use one. Think of it as the fuse to the fuel pump. Usually about 10A to 20A depending on the pump.

In addition there is normally a fuse for the alternator Sense wire close to the battery (see link below...).

3) Link

4) Have a look at the earthing for the 1GGTE, normally the intake manifold, engine block, etc are earthed also, and this is important. I don't see an issues with what you've described at a quick glance...

5) I can't think of any circumstances in a car when a relay with an inbuilt flywheel diode is likely to cause issues. That said I don't recall ever seeing a Toyota relay with an inbuilt flywheel diode, so not sure there is a need...



Some other notes:
>The engine EUC IGSW wiring doesn't look correct on your drawing...
>Not sure what is going on with you SC wiring (I've never had to look at this personally..), not sure it is correct?
>NSW wiring

Cheers
Wilbo

[ztd]

Hi Wilbo, thanks for taking the time to help me out with this. I'm very much an amateur - this is my first real foray into the electrical side of things but I'm researching and learning as I go Comments on your points:

1) I didn't see the connection from the alternator to the battery...the fuse is there, but I didn't see the connection to the battery!

I hadn't drawn that in yet, I don't really understand it to be honest so had avoided it! I have read your writeup on alternators, so that helps. I will re-do the sense line to have a fuse, but I'm kind of guessing with the power routing. Where do I actually take ignition-switched power from? I thought I could pull it straight off the alternator and run all my relays off that.

2) Fuses are usually sized to protect the wires. Do you have the 1GGZE wiring diagram with fuses sized? If not I'd probably look to use the 1GGTE fuse sizes.

I do yes, here's the one I'm using, it's for some flavour of 1GGTE. There is a 7.5A fuse between the ignition switch and IGSW pin of ECU, 7.5A between starter switch and ECU / Main EFI relay coil and 20A before the Main EFI Relay and 'BATT' on the ECU. The 7.5A ones I get, but the 20A one I don't - it's just hanging there in space... Am I right in thinking it's a permanent +12V direct from the battery? Other than that there are no fuses shown so I have to guess at the loads of the supercharger coil and thermofan (I got it with the car, no idea).

Also you don't need a separate fuse for the two COR relays, you can just use one. Think of it as the fuse to the fuel pump. Usually about 10A to 20A depending on the pump.

Is this the 20A fuse before the EFI Main Relay +12V terminal? I can see what you mean - the power coming in to the EFI Main Relay makes its way through the COR - if conditions are right - down to drive the fuel pump. My Fuel pump draws 10A, so that fuse should be 10A then (it also powers the Oxygen sensor though). I'll refine those in V2.

In addition there is normally a fuse for the alternator Sense wire close to the battery (see link below...).

3) Link

Thanks I will read, understand and add one in.

4) Have a look at the earthing for the 1GGTE, normally the intake manifold, engine block, etc are earthed also, and this is important. I don't see an issues with what you've described at a quick glance...

I'll see what I can see on mine, I don't have a running 1G to reference sadly so this one is a bit of a mystery. But if I can at least add one thick ground wire down to the chassis just for the fuse box that will be a good start.

5) I can't think of any circumstances in a car when a relay with an inbuilt flywheel diode is likely to cause issues. That said I don't recall ever seeing a Toyota relay with an inbuilt flywheel diode, so not sure there is a need...

That's good to know. None of the relays in the current fusebox have them, I just saw some advertised. These are no-name chinese relays, I'm going the same route but new, the price of 5x Narva or Tyco units is too much if cheap ones do the job (I also found out Hella are made in China anyway...)

>The engine EUC IGSW wiring doesn't look correct on your drawing...

On the GTE diagram it goes Ignition switch > 7.5A fuse > IG pin ECU. (I'm thinking IG is the same as IGSW?). Besides the fuse, did I leave something out? The idea is that IG sees voltage when the car is running.

>Not sure what is going on with you SC wiring (I've never had to look at this personally..), not sure it is correct?

This one I have had to work out myself a bit, and was why I was asking how to find out current draw for a device you don't have info on. ECU pin SMC grounds to earth when the ECU wants the supercharger on. So that is the trigger. I think you are right though, I've drawn it up wrong, it was a long night! Because there is no diagram for the 1GGZE I'm copying the 4AGZE setup, you can see it here. Club4AG

[ztd]

I've been working on the body loom while I wait for my fusebox gear to arrive, I will make v2 of the wiring diagram soon and post it up!

Am I right that for mock up purposes / just to get the engine running and prove that the fuel system works all I would really need to connect up are ignition circuits, starter and permaments 12v for the body loom?

[ztd]

OK so V2 is ready, it's attached here:

Hopefully it's readable, it's the best I could do in google docs.

http://imgur.com/XYPmCzm

It's separated into ECU, ENG (engine loom), CAR (car loom) and fusebox. I copied the fuse ratings from the 1GGTE wiring diagram rather than the RA28 one. Hopefully they work. I don't know the correct rating for the supercharger fuse so that will be a try it and see thing. I got my head around the negative triggering for that too.

The 2x COR relays are both getting their power off the main EFI relay. Is this a good way to run it or should I run a separate, fused power line to each instead and just the Main EFI relay as a signaler?

I think I've got every connection between the car and engine. There's so few, can that really be it?

One thing I'm scratching my head with is the oxy sensor - I traced the one wire coming off the sensor itself back to the ECU OXY pin. So that's the signal right? But the 1GGTE diagram shows the oxy sensor being a four-wire unit, needing 12v sent down to it from the main efi relay (which I've put in). But there's only one wire, how can it be both?