The fuel temperature sensor is located in the fuel supply system on the rear of the high-pressure pump.
It measures the fuel temperature in the low-pressure system.
With the aid of this signal, the fuel temperature can be continually monitored to prevent the fuel system from overheating.
Effects of faults (blue fuel temperature sensor)
Open control loop:
โข The system assumes a temperature of 39 ยฐC; the result is irregular, rough engine operation.
Short circuit:
โข If there is a short circuit, the system assumes a temperature of over 90 ยฐC (i.e. above the maximum permissible fuel temperature). In this case, the system assumes that the high-pressure fuel system is overheating. The engine cuts out or cannot be started.
Effects of faults (green fuel temperature sensor, obsolete)
In both cases, i.e. a short circuit or open control loop, the engine cuts out or cannot be started.
Diagnosis
The monitoring system checks:
โข the sensor for short circuit to ground/battery and open control loop.