2001 TOYOTA PRIUS Service Repair Manual

EM9891
± DIAGNOSTICSENGINE
DI±9
2001 PRIUS (RM778U)
3 Check air filter.
PREPARATION:
Remove the air filter.
CHECK:
Visual check that the air filter is not dirty or excessive oily.
HINT:
If necessary, clean the air filter with compressed air. First blow
from inside thoroughly, then blow from outside of the air filter.
NG Repair or replace.
OK
4 Check engine idle speed.
PREPARATION:
(a) Warm up engine to normal operating temperature.
(b) Switch off all accessories.
(c) Switch off A/C.
(d) Shift transmission into P position.
(e) Connect the TOYOTA hand±held tester or OBDII scan tool to DLC3 on the vehicle.
(f) Transit to inspection mode.
CHECK:
Use CURRENT DATA to check the idle speed.
OK:
Idle speed: 950 ± 1,050 rpm
NG Proceed to problem symptoms table on page
DI±22.
OK

A04438A13924A14466
TC
CG
A14060
DI±10
± DIAGNOSTICSENGINE
2001 PRIUS (RM778U)
5 Check ignition timing.
PREPARATION:
(a) Warm up engine to normal operating temperature.
(b) Shift transmission into P position.
(c) Keep the engine speed at idle.
(d) Using SST, connect terminals TE1 and E1 of DLC1.
SST 09843±18020
(e) Using a timing light, connect the tester to the ignition coil
connector wire (See page EM±11).
(f) Transit to inspection mode.
CHECK:
Check ignition timing.
OK:
Ignition timing: 7 ± 15° BTDC at idle
NG Proceed to page IG±1 and continue to trouble-
shoot.
OK
Proceed to problem symptoms table on page
DI±22.
6 Check fuel pressure.
PREPARATION:
(a) Be sure that enough fuel is in the tank.
(b) Connect the TOYOTA hand±held tester to the DLC3.
(c) Turn the ignition switch ON and push the TOYOTA hand±
held tester main switch ON.
(d) Use the ACTIVE TEST mode to operate the fuel pump.
(e) Please refer to the TOYOTA hand±held tester operator's
manual for further details.
(f) If you have no TOYOTA hand±held tester, connect the
positive (+) and negative (±) leads from the battery to the
fuel pump connector (See page SF±6).
CHECK:
Check for fuel pressure in the fuel inlet hose when it is pinched
off.
HINT:
At this time, you will hear a fuel flowing noise.

± DIAGNOSTICSENGINE
DI±11
2001 PRIUS (RM778U)
NG Proceed to page SF±6 and continue to trouble-
shoot.
OK
7 Check for spark.
PREPARATION:
(a) Remove the ignition coil (See page IG±5).
(b) Remove the spark plug.
(c) Install the spark plug to ignition coil and connect the ignition coil connector to ignition coil.
(d) Disconnect the injector connector.
(e) Be sure to ground the screw of the spark plug securely.
CHECK:
Check if spark occurs while engine is being cranked.
NOTICE:

Do not crash the electrode gap.

To prevent excess fuel being injected from the injectors during this test, don't crank the engine
for more than 5 ± 10 seconds at a time.
NG Proceed to page IG±1 and continue to trouble-
shoot.
OK
Proceed to problem symptoms table on page
DI±22.

DI±12
± DIAGNOSTICSENGINE
2001 PRIUS (RM778U)
7. ENGINE OPERATING CONDITION
NOTICE:
The values given below for ºNormal Conditionº are representative values, so a vehicle may still be
normal even if its value varies from those listed here. So do not decide whether a part is faulty or
not solely according to the ºNormal Conditionº here.
(a) CARB mandated signals.
TOYOTA hand±held tester displayMeasurement ItemNormal Condition*
FUEL SYS #1
Fuel System Bank 1
OPEN: Air±fuel ratio feedback stopped
CLOSED: Air±fuel ratio feedback operating
Idling after warming up: CLOSED
CALC LOAD
Calculator Load:
Current intake air volume as a proportion of max.
intake air volumeIdling: 5.4 ± 19.2 %
Racing without load (2,250rpm): 6.9 ± 16.2 %
COOLANT TEMP.Engine Coolant Temp. Sensor ValueAfter warming up: 80 ± 95°C (176 ± 203°F)
SHORT FT #1Short±term Fuel Trim Bank 10 ± 20%
LONG FT #1Long±term Fuel Trim Bank 10 ± 20%
ENGINE SPDEngine SpeedIdling: 1,000 rpm
VEHICLE SPDVehicle SpeedVehicle Stopped: 0 km/h (0 mph)
IGN ADVANCEIgnition Advance:
Ignition Timing of Cylinder No. 1Idling: BTDC 7 ± 15°
INTAKE AIRIntake Air Temp. Sensor ValueEquivalent to Ambient Temp.
MAF/AFMAir Flow Rate Through Mass Flow Meter
Idling: 1.11 ± 4.38 gm/sec.
Racing without load (2,250 rpm):
3.38 ± 7.88 gm/sec.
THROTTLE POS
Voltage Output of Throttle Position Sensor
Calculated as a percentage:
0 V "0%, 5 V "100%Throttle Fully Closed: 0 ± 5 %
Throttle Fully Open: 90 ± 100 %
O2S B1, S1Voltage Output of Heated Oxygen Sensor Bank
1, Sensor 1Idling: 0.1 ± 0.9 V
O2FT B1, S1Heated Oxygen Sensor Fuel Trim Bank 1, Sen-
sor 1 (Same as SHORT FT #1)0 ± 20 %
O2S B1, S2Voltage Output of Heated Oxygen Sensor Bank
1, Sensor 2Driving at 50 km/h (31 mph): 0.1 ± 0.9 V
*: If no conditions are specifically stated for ºldlingº, it means the shift lever is at P position, the A/C switch
is OFF and all accessory switches are OFF.
(b) TOYOTA Enhanced Signals.
TOYOTA hand±held tester displayMeasurement ItemNormal Condition*
MISFIRE RPMEngine RPM for first misfire rangeMisfire 0: 0 rpm
MISFIRE LOADEngine load for first misfire rangeMisfire 0: 0 g/r
INJECTORFuel injection time for cylinder No.1Idling: 1.0 ± 3.0 ms
CYL#1, CYL#2, CYL#3, CYL#4Abnormal revolution variation for each cylinder0 %
IGNITIONTotal number of ignition for every 1,000 revolu-
tions0 ± 2,000
FUEL PUMPFuel Pump SignalIdling: ON
EVAP (PURGE) VSVEVAP VSV SignalVSV operating: ON
VAPOR PRESS VSVVapor Pressure VSV SignalVSV operating: ON
TOTAL FT B1Total Fuel Trim Bank 1: Average value for fuel
trim system of bank 1Idling: 0.8 ± 1.2 V