P0187 - Fuel Temperature Sensor 'B' Circuit Low

System Information

The ECM can monitor the fuel temperature as part of the fuel / emissions control and also on some systems to determine whether additional fuel cooling (prevents vapour locks) or fuel heating (prevents diesel waxing) is required.

Fault Code Explained

The ECM has detected that the sensor output is below its minimum operating parameter or is lower than expected for the current operating conditions.

Recommended Tests

If possible use a diagnostic computer to compare live data readings for the fuel temperature sensor and compare to actual fuel temperature to establish if the sensor reading is correct

If the sensor reading is correct and the fuel temperature is too high:

If the sensor reading is incorrect: