3.3 Outputs 3 MS3PRO HARDWARE
eight channel Peak and Hold Injector Driver Board for use with low impedance injectors. Unused injector outputs
may be used for on/off outputs.
3.3.2 Ignition outputs
The MS3Pro uses 5 volt, logic level ignition outputs with a high side driver circuit. These will drive most factory
ignition modules and coils with built in ignitors. For use with coils that lack built in ignition modules, we recommend
the QuadSpark external ignition module. Note that these outputs will not trigger an MSD ignition box or a Ford TFI.
The tach output (see below) can be reassigned to function as a spark output when using these types of external
ignition modules. Do not connect the MS3Pro ignition outputs directly to the negative terminal of an ignition coil;
this can result in damage to the MS3Pro. Maximum current is 200 mA per ignition output channel, and pushing the
output beyond this amount of current can damage the output channel.
Unused ignition outputs may be used as on/off outputs, although their low current capacity means we do not
recommend using them for anything other than logic level devices or LED lights. Do not use these outputs to drive
relays directly or use them for anything that needs a ground for triggering.
3.3.2.1 Additional ignition outputs for V10 coil on plug applications For V10 (and 9 cylinder radial) coil on
plug applications, you can use PWM Out 2 as Spark Output I and PWM Out 3 as Spark Output J. As these outputs
normally do not produce 5 volts, you will need to add a 100 ohm, 1/4 watt resistor between the VREF and the
PWM Out wires in order to use these channels for spark outputs.
AMP EFI MS3Pro manual version 1.202, firmware 1.5.0, 4/21/2017 Page 26