05 -- 86
--
DIAGNOSTICS
ECD SYSTEM (1ND -- TV)
COROLLA Supplement (RM1129E)
DTC P0191 FUEL RAIL PRESSURE SENSOR CIRCUIT
RANGE/PERFORMANCE
CIRCUIT DESCRIPTION
The ECM c ontrols the internal fuel pressure of the c ommon rail by using the s upply pump and pressure con -
trol valve.
DTC No.
DTC Detection Condition
Trouble A reas
P0191
After c ertain period of time has elapsed after engine stop (pres -
sure control v alve releases common rail i nternal pressure dur -
ing this period), c ommon rail i nternal pressure deviates from
normal range.
(Determination of a malfunction is conducted within a given
time after the ignition switch is turned from ON to OFF. If a
malfunction is detected within this time, the MIL is illuminated
and a DTC is set when the i gnition switch is next turned to ON)
S
Open or short i n fuel pressure sensor circuit
S
Fuel pressure sensor
S
Open or short i n pressure control v alve circuit
S
Pressure control v alve
S
ECM
HINT:
DTC P0191 is set when the engine idles for 30 seconds after the ignition switch was turned to OFF.
WIRING DIAGRAM
Refer to DTC P0089 on page 05 -- 52
INSPECTION PROCEDURE
HINT:
Read freeze frame data using an intelligent tester ll. Freeze frame data record the engine condition when
malfunctions are detected. When troubleshooting, freeze frame data c an help determine if the v ehicle was
moving or stationary, if the engine was warmed up or not, and other data from the time the malfunction oc -
curred.
1 CHECK OTHER DTC OUTPUT(IN ADDITION TO DTC P0191)
(a) Connect an intelligent tester ll to the DLC3.
(b) Turn the ignition switch to ON and turn the intelligent tester ll ON.
(c)
Select the following menu items: Powertrain / Engine and ECT / DTC.
(d)
Read DTCs.
Result:
Display (DTC Output)
Proceed To
P0191
A
P0191 and other DTCs
B
HINT:
If any DTCs other than P0191 are output, troubleshoot those DTCs first.
B
GO TO RELEVANT DTC CHART
A
REPLACE COMMON RAIL ASSY (PRESSURE CONTROL VALVE AND FUEL PRESSURE SEN-
05MRU--01
To Alphabetical Index
To Sub Index
TOYOTA COROLLA REPAIR MANUAL SUPP 1129E