1jz wiring, ISCV etc

[wilbo666]

I tested resistance, each way was 47ohms (should be between 10-30?) Then I tested that the ISCV opens and closes using the method, which it does.

Then I tried testing continuity of each of the 4 'S' wires on the plug back to the ECU. Nothing... Is there something in the middle?
According to the diagram I have, and http://www.1jz.com/tech/docs/wiring/1jzecu_diagram.gif
S1/ISC1 = White-yellow
S2/ISC2 = Green-white
S3/ISC3 = Blue-red
S4/ISC4 = Red-black
None of the 4 wires could be traced to the ECU, so I'm going to have to pull the loom out and manually follow them.

Nothing in the middle...

You sure you had the right plug / pins? Maybe try all the plugs and pins just to make sure?

I don't think it would be real likely for all the wires to be cut, but the power wires to be OK still!

Cheers
Wilbo

[Jabtronic]

I think it was just a case of flat battery or something in my multimeter Once I pulled the loom out and rechecked they all worked

[ms53wagon]

so i had a bash at re-wiring the relay, seemed to go pretty well.

didn't make a difference on the first start up, still died if i didnt keep a little pressure on the gas (although it did start like normal which is a good thing).
however once i drove it to work and it warmed up it seemed to run/idle a little better although when i turned it off the engine kept running for like 5 secs then slowly spluttered and stopped haha!
could this be the m-relay connected to something else...

i connected what i thought was the relay power, but maybe its the actual power?

will have to have another look this eve.

just to confirm, the following should all have power when engine is on:
M-REL, B+, BT, IGSW

and when engine is off BATT should still have 12v

cheers again

[wilbo666]

just to confirm, the following should all have power when engine is on:
M-REL, B+, BT, IGSW

and when engine is off BATT should still have 12v

cheers again

M-REL is an OUTPUT from the ECU....it turns the relay ON/OFF. The ECU sends power out the M-REL pin to switch the main EFI relay on. The main EFI relay that is switched by this pin (the 'master relay') should provided the switched power to +B and +B1 which goes to the ECU, ISCV etc.

Yes +B, +B1 (there is no BT...it is +B1) should have power when the engine is on via the 'master relay' (which is switched via the ECU M-REL pin).

IGSW as I said before should have power when the ignition barrel is in run and crank.

BATT should have constant 12V power all the time (fused).


Also your injectors should be powered via a relay that is triggered off ignition (run and crank, the trigger for this relay should be the same as IGSW that goes to the ECU). This is a safety in case the ECU master relay gets stuck closed, you can still turn off the engine.

The igniter should also be powered with the same ignition switched power that is used to power the injectors.


Sit down, be methodical and work it out, do it properly and it'll be done!

Cheers
Wilbo

[ms53wagon]

success!!...of sorts

ISCV is now in working order! starts up like a dream in the cold!

the engine does still run for like 5 seconds after i turn off the key but im working on getting to the bottom of that.

couple of things i have noticed...

FC - open relay is not hooked up. (and there is no open circuit relay either). what is the functionality of this?

also my o2 sensor does not look like the wiring diagram, mine only seems to have one wire coming out (as opposed to the three shown in the wiring diagram). also nothing connected to HT (oxygen sensor heater) on the ECU.

cheers for all the help!

dan

[wilbo666]

A search will find you the following thread:
http://www.toymods.net/forums/showth...+opening+relay

That should spell it out

Cheers
Wilbo