RPS(Rail Pressure Sensor) used to transmit to the ECM the pressure value for the rail. The rail is a high pressure accumulator. In order to output a voltage signal to the ECM which is directly proportional to the applied pressure,the rail pressure sensor must measure the instaneous pressure in the rail.
The fuel flows to the rail pressure sensor through opening in the rail, the end of which is sealed off by the sensor diaphram.
Pressurized fuel reaches the sensor’s diaphram through a blind hole.
The sensor element (semi conductor device) for convertering the pressure to an electric signal is mounted on this diaphram.
The signal generated by the sensor is inputted to an evaluation circuit which amplifies the measuring signal and sends it to the ECM. This value is used in calculating the flow and injection advance.
In case of RPS failure, the engine symptoms will occur the running engine stall and the starting impossible.
If the signal is below threshold value, the ECM judged this as a fault and DTC is set.
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Signal check, low | ● Short to ground in signal circuit ● Faulty RPS ● Faulty ECM |
Enable Conditions | ● Engine run | |
Threshold Value | ● Output signal < 180.8 mV | |
Diagnostic Time | ● 0.18 sec. | |
MIL Fuel Limit Fuel Cut EGR Off | ● Yes ● Yes ● No ● No | |
Fail safe | ● Rail pressure is fixed at value of 400 bar by ECM. ● Engine shut down ● Starting impossible |
RPS | ||
Engine idle state | Fully acceleration (100%) | |
Rail Pressure | 220 ~ 320 bar (22 ~ 32 Mpa) | 1500 bar (150 Mpa) |
Signal Voltage | Below 1.7 V | Approx. 4.5 V |
