IGT or IGF cuircuit of ignition system Fault

azerty

Supermoderator
I went for a diagnostic yesterday.
I got this : IGT or IGF cuircuit of ignition system Fault
any idea what could be the cause ?
distri again ?
 

Texx

Admin
Could be a dizzy, igniter, wiring or ECU fault. First thing to do would be to check the continuity and resistance of the wiring from the dizzy and igniter back to the ECU.
 
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HYBRID

Super Moderator <a href="http://www.toyotagtturbo.
do as texx suggested lio.. but in all honesty it sounds like ur igniter is not working 100%
 

azerty

Supermoderator
Thanks guys, I would need an electrician who knows about resistance then...
The new dizzi I have is second hand, so it could just be dead as well.
I had a spare igniter that I sold not so long ago :( RRRRrrrrr
anyway, at least i know where to start

thanks, Rep added
 

Texx

Admin
If you've got a multimeter or have access to one, it should be easy enough for you to check yourself. It would be worth it at least to check the resistance on both the IG Timing and IG Feedback wires before paying someone to have a look. I can't tell you the wire colours, but you should be able to work them out by looking at the wires coming out of the igniter connector. They should connect to the ECU at connector 1 (the big multiplug connector), IGF should be pin 3 and IGT should be pin 22.

Unplug both the bigger ECU multiplug connector and the igniter connector. Then set the multimeter to the lowest ohms setting and probe both ends of each wire in turn. You may need someone to help you with this as it's difficult to be inside and outside the car at the same time. If you've got continuity and testing the right pins, you will get some sort of reading on the meter. If you get a reading of more than 0.2Ω then the resistance in the wire could be interrupting the signal between the igniter and ECU resulting in an intermittant fault. If you see no reading at all, then either your probing the wrong pins or there is a break in that wire between the igniter and ECU, usually a 'wiggle test' of the wire harness will be enough to remake the connection and show a reading on the meter, if you can pinpoint the point of the break, you can just chop that piece of wire out and bridge it back together with some more wire.

When you probe the pins in the connectors, particularly the ECU connector, you need to touch the probes at the front of the pins where they make contact with the component pins, make sure you don't damage the pins with the probes, a paperclip can come in handy here. The wires may not have high resistance, but their connection to the pins could so this needs to be checked.

If your happy with your test results, I would try another igniter and see if the fault clears.

I hope that makes some sense. :)
 
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Chathura Gihan

Fresh Recruit
I went for a diagnostic yesterday.
I got this : IGT or IGF cuircuit of ignition system Fault
any idea what could be the cause ?
distri again ?
Hi
Have you solved the problem? Because I am having the same issue and need to get it fixed.
Thanks
 

Jay

Admin
I would usually just get a donor vehicle and work off that but as Texx states above the wiring checks would rule out that side of things if you don't have access to such a vehicle.
 

SKINY

Lifer
I have had thís code with gen 5 celicas in the past, one of the pain in the ass codes :mad: dizzy, coil, ignitor,ECU "area" the big green book(workshop manual) says, it also has a section called electrical testing with a multimeter, it tells you how to test every component of the ignition circuit for faults:cool: handy if wee had a starlet manual the same ?
One I worked on every bit was in spec but turned out the timing belt had gone meaning no signal from dizzy to ingnitor etc

Old wiring I've also had issues with, it wasn't Toyotas strong point, had to fix lots of celica wiring in the past and I've seen the same in both the 98 glanza rep and the 95 by :rolleyes:
It's a "Toyota thing " :)
 

azerty

Supermoderator
That was 9 years ago. I forgot :/
I had an emanage ultimate at that time. so could have been a bug with it.
I have changed coil at least twice. could be that too
 
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