Cummins ISB CM550 (1990-94) Fault Code: 261 PID: 168 SPN: 174 FMI: 0 Pump High Fuel Temperature Error/Overheat Error

Circuit Description
The fuel temperature sensor is located in the fuel pump. Fuel temperature information is
passed to the engine control module (ECM) through the controller area network datalink.

Component Location
The fuel temperature sensor is located in the fuel pump.

Shop Talk
This fault code is typically set when the fuel pump controller communicates to the ECM that the fuel temperature measured in the fuel inlet to the pump (temperature sensor) exceeds the allowable threshold value (93°C [199°F]). This signal does not set a final temperature defect in the controller and, in most cases, identifies a fuel overheat condition on the engine/vehicle.