Tachometer: Description and Operation

When the ignition switch is on ON (II) or START (III) battery voltage is supplied through fuse 1 to the gauges in the gauge assembly. The gauge circuit is grounded at G401.

Tachometer
The tachometer drive circuit receives pulses from the ignition coil. The solid-state tachometer then displays these pulses as engine speed. For each 200 pulses per minute from the ignition control module (ICM) the tachometer displays 100 RPM.