magnetic pickup in dizzy, which wire is + which is -

[love ke70]

morning fellow car nerds
well as per topic this probably sounds like a dum/easy to solve problem.
and probably to those who know it is very simple, however, im stumped


thats the dizzy and as you can see there is a brown and a white wire that comes out of the sensor, these currently run away to the little ignition box as seen here:



however the issue is i have got a mallory hyfire VI igntion system (yay) and on the wiring diagram it has a black wire for the negative signal wire from the dizzy pickup and a green wire for the positive. and i cant for the life of me work out which is which.
i have tried just putting a multimeter from each wire to chassis when the ignition is on but car not running. they both read a positive voltage.
so thinking "the neg one will go to zero when it sparks, like on the coil" i turned the engine over by hand a few rotations on each one trying to see the volts drop on one...all to no avail
so now im stumped, did i miss something or do something wrong or is there another way i might be able to check?
cheers, andrew

[CHB]

this look like a 6 cylinders?

[oldcorollas]

is the ignition unit for a reluctor pickup? or for hall or or?

it's actually not that simple

with reluctor. you one wire being positive and then the other.. since you are creating current flow in one direction as magnet approaches coil, and then the other way as it moves away.
on a scope, you see this as a single AC wave at each trigger event.

if you can change if the ignition unit triggers on the positive or negative slope, then it may not matter, but if you can't then it may affect the actual timing of the ignition unit, relative to the dizzy...

for toyota units, if it is hooked up the wrong way, there will be ignition issues around? 5000rpm?? (can't remember exactly).

any/many of the wiring diagrams of cars using that style of reluctor pickup should have the polarity on it (perhaps?)

[takai]

Im pretty sure that the orange wire will feed you rising edge, and the white wire will be ground.

Either way, if you get it backwards it wont specifically hurt anything, itll just run like crap when the rpm increases to the point at which the overlap doesnt let the falling edge dip enough. I think on a 4cyl thats around 4500rpm, but on a 6cyl it woudl probably be lower.

[The Witzl]

You need to read my posts in this thread, BADLY!!! (nb - possibly some of my best work ever)

http://forums.toymods.org.au/index.p...art=0&count=60

Variable reluctance signals can be either "Falling Edge" or "Rising Edge"

Falling Edge = signal goes positive first
Rising Edge = signal goes negative first

This is an example of a Rising Edge signal, as specified as being required for a Wolf3D ECU.




Toyota reluctance sensors go positive first, meaning they are falling edge trigger.
You really need an oscilliscope to confirm how you've wired it correctly.... BUT - from the dissy:

WHITE = signal earth
PINK = signal
(in the standard toyota method of wiring, giving you a Falling Edge signal)

If you wire this in reverse, then you get a Rising Edge signal.

[love ke70]

yes, yes it is 6 cylinders. 'tis a 1ggte

stew, i have no idea about whether its for reluctor or anything else. i took the dizzy to hardcore performance racing. they took it to their supplier. i went in the next week and picked up "the unit which should work with my setup no worries." so im sure it will work as long as i get the wires right...eek! lol

so either way i hook it up it _will_ work, i may just have some issues with it.

and as takai has said it will just cough and fart. if it does that swap it around and all should be sweet again right?

oh, this is the diagram im working off



so just to clarify..im not going to break shit if i get it wrong am i?
cheers again guys

[The Witzl]

.... this is like the 3rd time i've answered this in a week! Time for a FAQ quide methinks!

[The Witzl]

re. your pic - *insert "CANT SEE SHIT CAPTAIN" pic here*

[oldcorollas]

oh, this is the diagram im working off

so just to clarify..im not going to break shit if i get it wrong am i?
cheers again guys

geez, ask them for a bigger picture

at worst, you will be igniting earlier and spark will have issues at rpm.
however, since you set the base timing (i would hope ) then regardless of the orientation, it should be ok.
if you swap around, you might see a change in the advance... i would guess that if it is the correct way, swapping it will advance a little...

TeH Witzl rulez!!

[love ke70]

phew, computers hurt my head
uploaded that 3 times before it didnt come out munted

anywho, thats the diagram im working from, now reading that link witzl

but consensus is pink will connect to green + on the diagram
and white will connect to black -
and all should be sweet?
sorry for asking if its been covered before...

[love ke70]

my brain hurts, but i think ive got this covered
shall let all know when its all wired up