Crimestopper Security Products RS1905FM - Manual (Page 17)

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TACH PROGRAMMING & TACH SIGNALS
INTRODUCTION
Tach signals will vary in levels and frequencies depending on many factors including the type of vehicle and the source of
the signal. The signals from a vehicle’s injector wire and coil pack wire can vary greatly even on the same engine. The
tach signal from an engine can also be affected by other sources such as electronic noise from the ignition or computer
modules. Recent improvements have been made to the circuitry to allow this CoolStart system to sense a wider range of
tach signals than previous models.
TACH MODE
The Tach mode provides reliable remote starting performance through engine speed (RPM) sensing. When using Tach
Reference Mode, the WHITE/RED wire is used for Tach signal [Engine RPM] input. Most modern engines include various
points where the Engine Speed [Tach] or A/C signal may be obtained. Tach Signal examples: Negative (-) side of ignition
coil, at the Distributor or Ignition Control Module, Coil Pack, Engine Computer, or Crankshaft Sensor. Sometimes Fuel
injectors and Alternator stator pins can be used. These Tach Signal locations mentioned are provided as a guide. Your
vehicle may differ. Some locations will NOT be a good location for Tach source due to RF noise or Computer Data.
TACH PROGRAMMING:
1. Open hood (or ground Blue hood pin wire if no hood pin is installed.)
2. WHITE/RED wire should be connected to a valid Tach source.
3. Start engine with key. (Pink wire must be connected!)
4. Press program button 5 times, then wait for 5 light flashes and/or 5 horn honks.
5. Push program button more once. (You must get one light flash and/or honk after button is pressed.) This unit is
now at option #1-Tach Learning.
6. Press the #1 Lock Button on remote transmitter. The unit will read the Tach source and flash the lights and or
honk once for program confirmation. (On RS1300DP models without remote transmitters, press the brake pedal in
this step.)
7. If lights do not flash for confirmation, then try another tach source or try the tach finder to locate another wire
EXAMINING THE TACH FREQUENCY WITH A DIGITAL MULTI-METER
If you own a Digital Multi-Meter meter with a frequency counter setting, it can be helpful to measure and research the range of tach signal
from your particular engine. When probing your chosen tach wire, observe the frequency reading from the meter at both the warm/low
engine idle and cold/high engine idle points. Tach signals ranging between 70Hz and 700Hz are desired. If your tach wire has readings
that are not in this range, the unit may not operate properly. The frequency of the tach wire in this range does not guarantee operation. If
you cannot locate a good tach source from your engine, then you can switch your CoolStart system to the “Smart Tachless” or “Timed
Crank”.