Cummins ISB CM550 (1990-94) Fault Code: 386 PID: SID 232 SPN: 620 FMI: 3 Sensor Suppy Circuit

Circuit Description
The engine position sensor (EPS), the intake manifold pressure sensor, and the oil pressure
sensor are powered by the same +5-VDC source and the same return in the electronic control
module (ECM). This supply is also used to operate the intake manifold temperature and
coolant temperature sensors.

Component Location
The +5-VDC sensor supply circuit is located in the sensor harness. See Section E of this
manual for the sensor locations.

Shop Talk
These faults could also cause high- or low-voltage faults on the coolant temperature and intake
manifold temperature sensors.