Cummins ISB CM550 (1990-94) Fault Code: 135 PID: 100 SPN: 100 FMI: 3 Oil Pressure Sensor Circuit

Circuit Description
The oil pressure sensor is used by the electronic control module (ECM) to monitor the lubricating oil
pressure. The ECM monitors the voltage on the signal pin and converts this to a pressure value. The
oil pressure value is used by the ECM for the engine protection system.

Component Location
The oil pressure sensor is located on the engine block, below and to the right of the ECM.

Shop Talk
1) If Fault Code 143 or 415 is not present, the problem is not related to the engine lubrication
system.
2) Your diagnostic tool can be used to monitor the oil pressure signal voltage going into the ECM.