EDI DIAGNOSIS SERVICE MANUAL NUMBER 22
Page 5E-26 90-860074--1 FEBRUARY 2002
RPM (Engine Speed) Sensor
Scan Code: P0725
Blink Code: 1131
Malfunction Indicator Lamp: ON
ECM
21
8
75311
1
2
3
123
WHT
BRN/RED
a
b
c
d
e
a-RPM (Engine Speed) Sensor
b-Harness Connector
c-Sensor ECM Input Signal
d-Sensor Ground (–)
e-Symbol for Shield Cable
CIRCUIT DESCRIPTION:
The rpm (Engine Speed) Sensor is an induction-type pulse generator which mounts close
the leading edge of the flywheel. Four notches (drilling) serve to sense the engine speed.
The resulting change in magnetic flux induces an AC voltage signal which is evaluated by
the ECM. The ECM processes the signal to establish TDC and the crankshaft position
relative to TDC.
A failure in the rpm sensor circuit should set a Scan Code P0725.
CKT PIN
NAME
8 ECM Input Signal from rpm (Engine Speed) Sensor
21 Sensor Ground, (Digital –)