Ascender 4WD L6-4.2L (2003)
Tachometer: Description and Operation
Tachometer
The IPC displays the engine speed based on the information from the PCM. The PCM converts the data from the engine speed sensor to a 2
pulses/engine revolution signal. The IPC uses the engine speed signal circuit (2 pulses/engine revolution) from the PCM in order to calculate the engine
speed. If the IPC detects a malfunction in the engine speed signal circuit, the IPC uses the class 2 message from the PCM indicating the engine speed.