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Discussion Starter #1
Hi there.

Need to know the input-output voltage of the distributor Hall sensor for 1.8 turbo one, it´s +5v or +12v? what about the V6 ones?

I can´t get the voltages on my own now, need them for a megasquirt conversion.

Thanks in advance
 

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i believe you need to supply the hall effect + and - pins with an EXCESS of 7.8Volts. When the pin marked '0' 'triggers' you will typically see around 8 volts, dropping to 0V in a square-ish waveform with frequency changing (with RPM of course).

This is what i have read 'in theory' but on an ignition project on another car with hall effect (saab 900) it seems to supply 12V ish to +/- pins, as well as a back voltage to pin '0'??? to charge the coil (similar to a dwell function?) or something...??

Ive decided to pull my oscilloscope to find out once and for all tho, as i cant get this particular project to run off BOSCH EZK ignition for some reason.
 

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Searching megasquirt projects with EZK ignition (saab....) it seems that you are right about the 8v, it´s the voltage that the EZK ecu gives, but people talk about that you can supply 12v whithout problems.

Maybe putting a 1N4738 8.2V zener diode for safety reasons?

Also they put a pull up resistor to bring good signal to the Ms Ecu between the + and the out signal of the hall sensor.

Have to check all of this in the EZK of the 75 turbo.
 

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i know in my case that my EZK supplies around 12 volts, and 13.8 while running, so it would seem to be simply battery voltage for the supply. no zener diode needed.

ALSO: Be careful of which ignition amplifier you are using!!! There are units with and WITHOUT dwell compensation. If you are not compensating for dwell in some way in MS, you will misfire at high RPM and eventually coil WILL blow up! cars with EZK have the NON DWELL units or BOSCH '124' module, whereas the conventional ignition cars will have the BOSCH '139' module with Dwell compensation. some EZK (and other digital control units) are dwell smart...im sure you have read up on this anyways, but just a warning...
I also have no idea what type of ignition is on a 1.8 turbo either.
 
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