Jegs 40824 Installation Instructions

Installation Instructions for 40824
RPM Window Switch with Push Buttons & Digital Readout
NOTE: Before beginning the installation of this kit please disconnect the positive battery cable from your
vehicle and read all the instructions completely!
Installation:

Power - Red wire attaches to a switched +12 Volt supply source.

Ground - Black wire attaches to chassis ground.

Tach Input - Grey wire is input for the Tachometer signal. This wire will hook up to the negative side of your ignition
coil, or if you are using a high energy CD ignition, connect the Grey wire of the RPM switch to the TACH output of
your ignition system and NOT the coil.

Tach Output - Blue wire connects to the negative/ground side of the device that you want to activate at the desired
RPM.
Warning: Most Late Model vehicles that don't have a distributor, or have multiple coils will require the use of a
Tach Adapter.
If the device to which the blue wire is attached to draws more than 3 amps, a relay must be used to drive that
device or damage will occur to the unit.
If your vehicle has a separate ignition coil, connect the gray wire to the negative (-) side of the coil – the wire that
goes to the points or electronic ignition module.
If your vehicle has a GM HEI ignition, connect to the terminal marked 'TACH', or, on some systems, a single white wire
with a spade terminal.
If your vehicle has an after-market ignition – some systems will connect to the TACH output terminal.
If your vehicle has a computer controlled ignition system, consult the service manual for the wire color and location.
If your vehicle has a magneto system, connect the tach signal wire to the negative side of the coil. Do not connect the
tach terminal to the positive (+ or high voltage) side of the ignition coil.
This connection is either Normally Open (Blue wire provides ground AFTER the switch reaches desired RPM) or
Normally Closed (Blue wire is grounded UNTIL switch reaches desired RPM) according to the setting in program mode
(OFF means Normally Open and will supply ground when the selected RPM is reached, ON means Normally Closed
and the switch will open when the selected RPM is reached). Factory default is Normally Open.
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