US Shift Quick4 4R100, Installation And Operation Manual

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In some cases, such as driving the input of an engine control ECU, the 0-12 Volt
square wave signal will not be able to properly drive the device that it is
connected to. This is because some devices are only designed to accept an
input signal from a variable reluctance (magnetic coil) sensor. Because of this,
they may expect the input signal to swing below ground (0 Volts). To drive this
type of input, use the 5 Volt AC signal mode. In this mode, the driven device will
see a -2.5V to +2.5V signal.
Shift-in-Progress
The shift-in-progress output is used to implement torque management
functionality during shifts. When a shift is occurring, this output will be pulled to
ground as a signal to the engine management system or ignition timing control
device to reduce torque by managing ignition timing, throttle plate angle, boost
pressure, or, for diesel engines, fuel. In some cases, a "pull-up" resistor to 5V or
12V may be needed to provide the proper input to the controlled device. Please
contact US Shift tech support if you have any questions regarding the
connection of this signal.
Engine RPM Signal Input
The engine RPM signal input on the yellow lead (pin 7) can be connected to a
digital tachometer output from an engine computer or the tachometer output
from an MSD ignition or similar CDI (Capacitive Discharge Ignition) system, but
NEVER to the coil outputs of a CDI system like MSD.
For breaker points (or conventional electronic ignition systems such as GM HEI,
Ford Duraspark or TFI), it can be connected to the coil negative terminal. For
this configuration, add the supplied 47K Ohm resistor (yellow, violet, orange,
and gold bands) to the yellow lead (pin 7) in-line with the tachometer signal. The
correct setting will need to be set in the tuning software under Settings>Speed
Sensor & Gearing.
For COP (Coil on Plug) ignition systems that do not have a conventional
tachometer output (such as later Mustang engines), one of the coil trigger wires
can be used, but the update rate will be slow. A better approach for such
applications would be to use a tachometer adapter such as the AutoMeter 9117.
DO NOT run the engine RPM signal wire in the same wiring harness as the
speed sensor as this can cause interference.