3T distributor Variable Reluctor sensor

[CHB]

i'm going to wire up my Megasquirt II on Ver 3 board and run single coil ignition setup from it. i came out one problem.
there are 2 wires from the VR sensor, Red and White. which one is positive and which one is negative?
any one here running a 3TC on megasquirt?

[thechuckster]

i ended up borrowing wilbo's scope to work this out (i used the guts out of a 21RE - i think - in my dizzi) - give me a day and i'll be able to tell you which is what.

i'm running th earlier MS board with MSnS.

[CHB]

i ended up borrowing wilbo's scope to work this out (i used the guts out of a 21RE - i think - in my dizzi) - give me a day and i'll be able to tell you which is what.

i'm running th earlier MS board with MSnS.

how was it? any updates?

[thechuckster]

sorry, got distracted...

My VR sensor has brown and white wire (those wires gets soaked in oil on most engines so the colour fades/changes a fair bit) and they're hooked up as:
brown - VR+
white - earth

Am using the LM1815 conditioner circuit (see <http://megasquirt.sourceforge.net/ex...tup-wheel.html>, scroll to heading "LM1815 based VR sensor conditioner for V2.2 or v1.01").

I didn't use the 'optional' 390R resistor across the input. I run the 'earth' trace right up to this circuit, plus i ground the shield of that cable at the same point. Cable is microphone cable (2 wires, single shield, thick rubber insulation).

cheers,
Charles.

[CHB]

thanks for the info. but the setup you've used is only for MS1 on 2.2 board right and it does not apply in Ver3 board right?

[The Witzl]

pcb3.0 has the VR conditioning circuit on-board iirc - just make sure the cable has minimal unshielded length, and the shield is grounded at only one end... and read the megamanual

and Chuck is correct - white is ground, pink/red/brown is signal.

[thechuckster]

sorry about the confusion - the v3 PCB has an analog zero-crossing/conditioning circuit on-board - having a v2.2 board meant making my own and i got lazy and went the monolithic chip route ;-)

The cabling is the same, is just the actual board hardware that differs.

cheers,
Charles.

[CHB]

thanks for the tips... u guys r owesome/...

[J-M kujala]

topic after years, but only place where i found topic at 3TC VR with Dizzy... so anyone use stock Dizzy with STOCK V3 board ? mine ECU is from DIY autotune and dont get it work, anyone else got them work together without modifications ?

[CHB]

yes that is what I did. Did you got your assembled from DIYAutotune? if so which MS is it? MS1, MS2 or MS3?

The easiest way is using stock toyota ignitor to convert the Alternating signal from VR sensor into 5V square wave. By doing this you get a clean signal that will travel from your distributor right into MS with no problem at all.

If you don't know how to do it please let me know, I'll show you the step by step method.

[thechuckster]

J-M kujala: before attacking the VR circuit on the V3 board, just check that the VR sensor isn't open circuit, and that the air-gap between tooth & sensor is less than 1mm (can't recall what I set mine too in my old 28RTE but figures of 0.5mm or less come to mind - if you can find a TSRM for a 22RE or similar engine that uses that 4-tooth trigger wheel and VR sensor, just use their specifid air-gap).

edit: 22RE electronic dizzi is .008-.016 inch air gap.

Would suggest you take dizzi off the motor, set it up so you can drive it with a drill (connect the drill to it with piece of rubber hose (sitting over a drill bit) - either direct drive it or simply press the rubber hose up against the side of the shaft). The onboard VR circuit on the v3 board is this:
http://www.msextra.com/doc/ms2extra/...gnition.htm#vr

note that R56 & R52 are adjustable - allowing you to 'tune' the signal from the VR sensor.

Use the trigger logger (either in Megatune or TunerStudio) to check that you are getting triggers, and then adjust the zero crossing point and hysteresis as required.

Start reading here: http://www.diyautotune.com/tech_arti...t_vr_index.htm

From http://www.msextra.com/doc/ms1extra/...anual.htm#vrin

Adjust both the pots fully counter-clockwise (ccw) as a starting point, they don't physically stop turning, you will hear them click when they are fully one way. Generally the pots end up either fully ccw or a few turns clockwise from there.

[J-M kujala]

HI damn this cant post

[J-M kujala]

haha quick reply do not work for me...


i have done just like manual says... try different sensors and with drill also, i have many Dizzys so its not problem.... now have Fighting 2 FULL days with this issue..

ECU was already assembled in Diyautotune, so there is no Modofications, only jumpers.... mine is with mS1 processor... i think it will be easyer for fisrt timer, and OK For 3T N/A Setup..

[J-M kujala]

yes that is what I did. Did you got your assembled from DIYAutotune? if so which MS is it? MS1, MS2 or MS3?

The easiest way is using stock toyota ignitor to convert the Alternating signal from VR sensor into 5V square wave. By doing this you get a clean signal that will travel from your distributor right into MS with no problem at all.

If you don't know how to do it please let me know, I'll show you the step by step method.

haha just when i wake up, i start to think that Original igniter, how it would work... it will make same thing than HEI4 Module ?

[oldcorollas]

i'm using an original ignitor (Bosch, from AE82 corolla) with 1k resistor from +12V to the signal (coil) wire of the ignitor as a pull-up resistor...
but..

you should be able to use your VR directly with the V3 board..
do you have the jumpers set up correctly?
what have you been trying so far?