Haltech E6A - Manual (Page 122)

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through the Ignition Setup [4.6.1], which makes the output suitable for ignition systems that
do not need dwell control.
G.M. Direct Fire Ignition
The G.M. Direct Fire Ignition module (DFI), as used in the V6 Buick, can be connected
directly to the E6A ECU. This module serves both as a trigger device and as an igniter. For a
wiring diagram, see Appendix G. The DFI module has an ignition bypass input from the ECU.
This input tells the DFI module to ignore the ECU’s timing signal and fire its own spark at 10°
BTDC. This gives a more reliably timed spark for cranking. This input is controlled by the E6A
through the Aux. In/Out Function. To use the bypass, this function should be set in the
Identification to Bypass. See Chapter 3 [3.1]. The bypass will allow the DFI module to control
spark below 450 rpm
Ford Thick Film Ignition (TFI)
The Ford TFI module is fitted to distributors used with Ford’s EEC IV engine management
computer system. The E6A ECU can connect directly to this module, however, the TFI
module requires a trigger signal, call the SPOUT (see next page), that has a 50/50 duty cycle,
which is not the standard 70/30 duty cycle of the E6A. To use the Ford TFI module you will
have to adjust the Ignition Output Duty Cycle in the Ignition Setup (see Chapter 4 on
Accessing the Ignition Map) to 50.
Signal Names for TFI Module
PIP Profile Ignition Pickup Output
(trigger pulses from the Hall Effect Sensor)
SPOUT Spark Out (Igniter output from the ECU) Input
POWER + 12 volts from starter circuit Input
POWER + 12 volts from ignition switch Input
COIL - Negative terminal of coil Output
GND Ignition system ground
There are several versions of the Ford TFI module but these notes only refer to the type IV
module. This TFI module is physically attached to the side of the distributor and connects
directly to the HALL Effect pickup within the distributor.
To further complicate matters there are two types of chopper wheels used inside the
distributor, one that generates a normal’ PIP signal and one that generates a ‘signature’ PIP
signal. With the signature PIP, the pulse for cylinder one is sorter than the pulses for the
remaining cylinders. This is similar to Figure E.3 except that the cylinder one pulse is shorter
rather than longer. Unfortunately the edges where the pulses do coincide occur at 10° BTDC.
Therefore the E6A cannot be used with a signature PIP unless the trigger point is moved. If the
trigger is modified be wary of rotor phasing (See Appendix F). The trigger edge for the Ford
TFI module is falling edge. For 8 cylinder engines the Trigger Angle is 55° and for 6 cylinder
engines it is 70° BTDC.