What is tach input?

What is tach input?

“Tacho” inputs are designed to be connected to existing Tacho signals from either the Alternator (“W”, ”R” or “AC”) terminal, an inductive Tach sender, an ignition coil or – a hall-effect Tacho sender.

What is the tach signal?

The vehicle’s Tachometer signal tells the iKey system how fast your engine is running. The iKey uses this information to determine how long to crank the vehicles Starter as well as to determine if the vehicle is running or not.

How does a tach signal work?

Tachometers, in their most basic forms, are devices that measure the speed of an object. Most commonly, they measure the rotation of a mechanism, like the engine shaft in a car. Traditionally, tachometers are dials with a needle pointing to the current speed in RPMs (revolutions per minute).

Do I need a tach adapter?

If, after installing an MSD Ignition Control, your tachometer, fuel pump relay or electronic fuel injection (in foreign vehicles) doesnt operate correctly, your application may require a Tach Adapter. This is due to the trigger signal not being strong enough to trigger both the MSD and the factorys components.

What does a tach adapter do?

The Auto Meter Tach Adapter wires in line on the positive 12 volt supply wire. It senses current on the coil positive wire and converts it to a 12 volt signal output. The Tach Adapter is designed to be mounted under the hood. The circuits are potted in polyurethane for water resistance and vibration protection.

How do you get a tach signal?

Set the meter to AC voltage. Connect the negative Meter lead to a good chassis ground in the vehicle and the positive lead to the suspected tachometer wire. Start the vehicle and wait for it to idle down to normal idle speed. At this point the meter should be displaying a fairly constant AC voltage.

Where does an LS engine get its tach signal?

The Tachometer Adapter will wire in series between both banks of coils and their power supply. The adapter will not have anything to do with the trigger, or signal side of the coils. It gets wired in so that all ignition power (the 12v power supplied to the coils) is routed into, through, and back out of the adapter.

Why does my boat tach reads high?

An insufficient power or ground will cause a tachometer to actually read too high. By doing this, you will be looking at what the tachometer sees for power and ground, combined. If you measure below 12.0 volts, identify which connection is the problem, and correct it.

How does a MSD tach adapter work?

Each adapter is simple to wire in and will have your MSD and vehicle firing away in no time. The PN 8920 will correct the operation of most voltage-triggered tachometers that do not work directly off the tach output terminal of the MSD control.