K11 loom resistor...what does it do?

[solarice]

ok for those of you whove spent some time looking at the wiring diagram for the micras, or just know what they are looking at...can you tell me what exactly this resistor does. (see pic its marked with a red square)

cos even with it removed from the wiring loom the tacho and the engine still run and idle fine...i was switching it out with another one to test, because it seemed to be causing the rpm spike fault...but now im not so sure (as it seems to do nowt and now im confused lol)

W/R wire goes to ecu pin 3 btw.

Cheers.

 

[frank]

i would hazard a guess at it being a balast resistor (ie, to drop the voltage to the (9v ?)coil once the engine has fired up)

 

[solarice]

mmm i had looked into it being a ballast resistor...but both sides of the resistor measure just over 12v (one side being slightly lower) when the ignition is on...and when the engine is running both sides are about 13.5v iirc (again one side being slightly lower)

This is even when using different resistors so it cant be a bad resistor.

 

[NeX]

when i was cutting my loom down i am pretty sure i cut this out as i followed the wires and they didn't go anywhere

 

[solarice]

They deffo go places Nex (on mine at least) white/Red to pin 3 on the ecu and the Green/Black wire goes to the Dizzy. (as ive traced them to make sure they were still good/connected)

But the Resistor as far as i can tell doesnt seem to do anything lol...unless something switches awhile after the cars been running.?

anyways looks like ive narrowed it down to having nothing to do with that anyway, so at least thats something...

 

[Noddie]

yes, i wondered what it did too,
I'm 85 percent sure that the wire is a signal wire to tell the ecu that the spark was successful. it is connected to the secondary negative on the coil and would have a pulse sent down it at the same time as the spark happens. there was no input for this wire on my standalone so i just cut it out.

 

[NeX]

They deffo go places Nex (on mine at least) white/Red to pin 3 on the ecu and the Green/Black wire goes to the Dizzy. (as ive traced them to make sure they were still good/connected)

But the Resistor as far as i can tell doesnt seem to do anything lol...unless something switches awhile after the cars been running.?

anyways looks like ive narrowed it down to having nothing to do with that anyway, so at least thats something...

well i was pulling apart a 1.0L pre nats loom, maybe they are different. i think one wire (white/red) was going to that multi connector for the engine loom, but not comming out the other side to go to the ECU, so i chopped it out.

but yea it could be a sacrafical resistor, we use them at work, they are resistors that are designed to burn out if there is too much power going through them but other than that they don't do much resisting. they are pretty much a fuse but built like a resistor.

if what noddie is saying about it comming from the coil is right, then that would make sense, you don't want a full on spark reaching the ECU

 

[s1adam91]

Anyone got the pin wiring diagram for a facelift 2 K11 ECU