Sierra 1500 4WD V8-5.3L VIN Z Flex Fuel (2005)
Tachometer: Description and Operation
TACHOMETER
The instrument panel cluster (IPC) displays the engine speed on the analog tachometer based on the engine speed signal from the powertrain control
module (PCM). The IPC uses the engine speed signal circuit-2 pulses/engine revolution-from the PCM in order to calculate the engine speed.
The tachometer defaults to 0 RPM if a malfunction in the engine speed signal circuit exists.
