Haltech F9A - Manual (Page 25)

24
1.3.10. Configure Trigger DIP - Switches
The input trigger is used by the F9 to determine engine speed and when to fire the injectors.
The standard connection for this wire is to the negative terminal of the ignition coil. If the
engine does not use standard points or a electronic ignition system then it may be necessary to
reconfigure the input circuit. The trigger configuration DIP switches can be found by
removing the back cover from the F9 ECU. Refer to the following tables (see below) for DIP
switch functions and settings.
Switch 1 ON: Adds 1k pull-up resistor to battery.
Use an open collector (digital) outputs.
Switch 2 ON: Engage primary filter capacitor.
Switch 3 ON: Engage secondary filter capacitor.
Switch 4 & 5: Changes trigger threshold level (see below)
Trigger level Switch 4 Switch 5
+5.0 Volts OFF OFF
+3.4 Volts ON OFF
+2.5 Volts OFF ON
+2.0 Volts ON ON
Refer to the following tables for switch settings for common ignition systems. All ECU’s are
factory set for Category A ignition systems.
Category A Category B Category C Category D
Points style MSD 6A/6T Firepower ECI Porsche 911/930
Transistor
MSD 7AL/7x Buick Indy
Assisted Direct Fire
Direct
Fire MSD 8 GM MSD
GM HEI Electromotive
Jacobs
Stinger
1
Stinger
Thermo-Fire
(Most
Others)