XJ-S Convertible (XJ27) V12-6.0L (1994)
Engine Speed Sensor: Description and Operation
Engine Speed Sensor
PURPOSE
The engine speed sensor supplies an engine rpm signal to the IGNITION ECM, which in turn relays rpm information to the EFI ECM.
OPERATION
The sensor is an inductive pick-up device triggered by flywheel ring gear teeth acting as a reluctor. Each of the ring gear's 160 teeth induce a signal
whose frequency is interpreted by the ECM as engine speed. Without speed sensor input, the engine will not start.
Engine Speed Sensor
LOCATION
On bottom of bell housing in position required to utilize flywheel teeth as a reluctor.