Component Location
Description
1. General Description
Fuel pressure monitoring is used to detect the troubles and the fuel leakage in high pressure system. The ECM determines the rail pressure value as a function of the engine’s operating conditions and controls the fuel pressure regulator to ensure that the rail pressure reaches the required value. Fuel pressure in the fuel line including the pumps and injector are continuously monitored during engine runing. If the rail pressure is excessive, the fuel pressure regulator opens and a portion of the fuel returns from the rail to the fuel tank via a collector line. If the rail pressure is too low, the Fuel pressure regulator closes. The fuel pressure regulator closes. the fuel pressure regulator is installed in the tail end of high pressure accumulator. In case of the insufficient fuel supply in the fuel line, the engine symptoms will occur a shut down and a starting impossible.
2. DTC Description
If an extremely low or high pressure in the fuel line is being read by the ECM during driving cycles, this code will be set .
DTC Detecting Condition
DTC NO. | Detecting Condition | Possible Cause |
P 1185 P 1186 P 1187 P 1188 P 1189 | Detecting Condition ? P 1185 Error is recognized if the rail pressure is above 1450 bar at the above 700 rpm of engine speed (Maximum pressure exceed) ? P 1186 Error is recognized if the rail pressure is below 120 bar at the engine speed from 0 to 2400 rpm and below 200 bar at the above 2800 rpm of engine speed after the engine starting (Governor deviation at the high engine speed ) ? P 1187 Error is recognized if the regulator valve duty ratio of fuel pressure is below 10 % and above 250 bar as against the actual target value of rail pressure.(Fuel pressure regulator sticks in closed position) ? P 1188 Error is recognized if the regulator valve duty ratio of fuel pressure is below 79 % and below 250 bar as against the actual target value of rail pressure. target value of rail pressure. (Fuel pessure regulator leakage) ? P 1189 Error is recognized if the actual value of rail pressure as against the target value of rail rail pressure is below 250 bar while supplying the maximum fuel quantity from the pressure valve of fuel regulator in proportion to the engine speed. (Minimum pressure at the low engine speed) ? Engine Condition : RUN ? Fuel Limit : YES ? Fuel Cut : YES ? EGR OFF : NO ? MIL : YES | ? Fuel filter ? Electric fuel pump ? Injector ? Rail pressure sensor ? Fuel pressure regulator ? High pressure pump ? Fuel leakage in ? Fuel supply ? ECM |
Specification
Test Condition | Normal parameter (Engine idling) |
Fuel rail pressure | 220 ~ 300 bar |