This instruction show you guide on how to solve Doosan and Bobcat rail pressure fault can occur due to failures in both the LPC(Low-pressure circuit:Fuel tank to HP pump) and HPC(High-pressure circuit : HP pump to injector). Therefore, it is usually necessary to check the following items.
| No
. |
Fault | Fault code | Detection description | Detection | Remark | |
|
1 |
Maximum positive deviation of rail pressure exceeded (DFC_RailMeUn0) |
P0002 SPN : 157 FMI : 11 |
If the rail pressure governor
deviation exceeds the limiting value(Normally 70~150bar) based on the engine speed and the set value of the Fuel Metering unit volume is greater than the upper limit, an error will be detected. |
Cranking Engine running |
2.5 sec |
|
|
Estimated Root cause |
– This fault could be detected when there is a lot of air in the fuel or the fuel is not supplied well.
1) When engine is continuously operated with very low fuel level.(or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel filter plugged 4) Electric fuel feed pump failure |
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|
2 |
Fuel Leakage is detected based on fuel quantity balance (DFC_RailMeUn10) |
P0087 SPN : 157 FMI : 10 |
If the high pressure pump
delivery quantity exceeds the plausibility limit of the volume flow balance (evaluated over the product life and supplemented to include tolerances), an error will be detected. |
Cranking Engine running |
2.5 sec |
|
|
Estimated Root cause |
– This fault could be detected when there is a lot of air in the fuel or the fuel is not supplied well.
1) When engine is continuously operated with very low fuel level.(or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel HPC(High pressure circuit – HP pump, common rail, injector) leakage (almost 10~25L/h high leakage) 3) Fuel filter plugged 4) Electric fuel feed pump failure |
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|
3 |
Maximum negative
rail pressure deviation with metering unit on lower limit is exceeded (DFC_RailMeUn2) |
P0254 SPN : 1076 FMI : 16 |
If the rail pressure governor
deviation falls below the limiting value(Normally -200~-117bar) and the high pressure pump delivery quantity falls to the threshold, an error will be detected. |
Cranking Engine running |
5.0 sec |
– Mainly occurs when HP pump return is blocked |
| Estimated Root
cause |
– This fault could be detected when the fuel LPC issue.
1) HP pump return line plugged 2) HP pump inlet pressure is too high (Electric fuel feed pump failure) |
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|
4 |
Rail pressure too low fault (DFC_RailMeUn3) |
P190C SPN : 157 FMI : 26 |
If the rail pressure falls below the limiting value(Normally 120bar) based on the engine speed, an error will be detected. |
Cranking Engine running |
2.5 sec |
|
|
Estimated Root cause |
– This fault could be detected when there is a lot of air in the fuel or the fuel is not supplied well.
1) When engine is continuously operated with very low fuel level. (or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel filter plugged 4) Electric fuel feed pump failure |
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|
5 |
Maximum rail pressure exceeded (DFC_RailMeUn4) |
P190B SPN : 157 FMI : 27 |
If the rail pressure exceeds the limiting value (Normally 1950bar), an error will be detected. |
Cranking Engine running |
1.0 sec |
|
|
Estimated Root cause |
– This fault could be detected when the rail pressure control is not performed properly due to a lot of air in the fuel.
1) When engine is continuously operated with very low fuel level.(or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel filter plugged 4) Electric fuel feed pump failure 5) HP pump metering unit failure 6) Rail pressure sensor failure |
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|
6 |
Fuel Metering unit plausibility error in overrun mode (DFC_RailMeUn7) |
P0004 SPN : 1076 FMI : 03 |
If the high pressure pump
delivery quantity exceeds the threshold based on the pressure at overrun mode, an error will be detected. |
Engine running at
Overrun condition only |
2.5 sec |
– Very unlikely
to occur because there is little overrun in machine operatio n conditio n. |
|
Estimated Root cause |
– This fault could be detected when there is a lot of air in the fuel or the fuel is not supplied well.
1) When engine is continuously operated with very low fuel level.(or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel filter plugged 4) Electric fuel feed pump failure |
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|
7 |
Fuel Metering unit plausibility error in idle mode (DFC_RailMeUn8) |
P0003 SPN : 1076 FMI : 04 |
If the high pressure pump
delivery quantity exceeds the threshold based on the pressure at idle mode, an error will be detected. |
Engine
running at Low idle condition only |
2.5 sec |
– Low idle only |
|
Estimated Root cause |
– This fault could be detected when there is a lot of air in the fuel or the fuel is not supplied well.
1) When engine is continuously operated with very low fuel level.(or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel filter plugged 4) Electric fuel feed pump failure |
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|
8 |
Rail pressure too low for injection (DFC_RailMonInjRls) |
P0252 SPN : 1076 FMI : 20 |
The rail pressure falls below the minimum threshold for injection. (100bar) |
Cranking Engine running |
0.5 sec |
|
|
Estimated Root cause |
– This fault could be detected when there is a lot of air in the fuel or the fuel is not supplied well.
1) When engine is continuously operated with very low fuel level.(or empty) 2) Fuel LPC(Low pressure circuit – Fuel tank, Fuel filter, Electric fuel feed pump) leakage 3) Fuel HPC(High pressure circuit – HP pump, common rail, injector) leakage (almost 10~25L/h high leakage) 4) Fuel filter plugged 5) Electric fuel feed pump failure |
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|
9 |
Pressure relief valve(PRV) failure (DFC_RailPRV4) |
P1934 SPN : 157 FMI : 28 |
The fault is occurred when If
PRV(Pressure relief valve) open fault (P000F) occurs but rail pressure does not decrease. There can be a problem with PRV itself. |
Cranking Engine running |
1.2 sec |
– Very unlikely to occur |
| Estimated Root
cause |
– PRV(Common rail pressure regulating valve) failure |
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