Page 1764 of 1943

± BODY ELECTRICALTROUBLESHOOTING
BE±7
1674 Author: Date:
2001 PRIUS (RM778U)
Warning Lights:
COMBINATION METER
SymptomSuspect AreaSee page
Warning light do not light up. (Except Discharge, Open Door and
SRS)
1. GAUGE Fuse
2. Meter Circuit Plate
3. DC/DC converter
4. Wire Harness±
BE±39
±
±
Fuel Level warning light does not light up.
1. Bulb
2. Meter Circuit Plate
3. Fuel Tank Assembly
4. Wire Harness±
BE±39
±
±
Low Oil Pressure warning light does not light up.
1. Bulb
2. Low Oil Pressure Warning Switch
3. Meter Circuit Plate
4. Wire Harness±
BE±42
BE±39
±
ABS warning light does not light up.
1. Bulb
2. ABS ECU
3. Wire Harness±
DI±351
±
Seat Belt warning light does not light up.
1. Bulb
2. Buckle Switch
3. Meter Circuit
4. Wire Harness±
BE±42
BE±42
±
Brake warning light does not light up.
1. Bulb
2. Parking Brake Switch
3. Brake Fluid Level Warning Switch
4. Meter Circuit Plate
5. Wire Harness±
BE±42
BE±42
BE±39
±
SRS Warning light does not light up.
1. Bulb
2. Airbag Sensor Assembly
3. Meter Circuit Plate
4. Wire Harness±
DI±495
BE±39
±
Open Door warning light does not light up.
1. DOME Fuse
2. Bulb
3. Door Courtesy Switch
4. Meter Circuit Plate
5. Wire Harness±
±
BE±27
BE±39
±
Indicator Lights:
COMBINATION METER
SymptomSuspect AreaSee page
High beam indicator light does not light up.
1. Bulb
2. Meter Circuit Plate
3. Wire Harness
4. Headlight System±
BE±39
±
BE±20
Turn indicator light does not light up.
1. Bulb
2. Meter Circuit Plate
3. Wire Harness
4. Turn Signal and Hazard Warning System±
BE±39
±
BE±25
Malfunction indicator light does not light up.
1. Bulb
2. ECM
3. Meter Circuit Plate
4. Wire Harness±
±
BE±39
±
Indicator lights do not light up. (Except Turn, Hi±beam and
security)1. GAUGE Fuse
2. Wire Harness±
±
Page 1785 of 1943
I17798
A20
A12
A14
A2
A3
A1
B7
B6
B1
A9
A11
A13
A22
A21
B2
B3Conversion
Drive unit
Correspon
dence
Buzzer
Power Supply
Circuit (VFD)
ECU
Drive unit
Open door indicator
Illumination
Brake warning
Driver seat belt warning
Low oil pressure warning
Discharge warning
CRUISE main indicator
Engine coolant warning (Low)
Engine coolant warning (High)
Passenger seat belt warning
Malfunction indicator
ABS warning
SRS warning
Left turn indicator
Right turn indicator
Hi±beam indicator B5
A19
A18
A17A15 A16 A10 B4 Output control indicator BE±40
± BODY ELECTRICALCOMBINATION METER
2001 PRIUS (RM778U)
Page 1789 of 1943

I17865
Fuel Sender Gauge Connector
I17865
Fuel Sender Gauge Connector
I01277
BatteryWarning Light Ignition
Switch
Wire Harness Side
1
I01278
BE±44
± BODY ELECTRICALCOMBINATION METER
2001 PRIUS (RM778U)
5. INSPECT FUEL SENDER GAUGE VOLTAGE
Measure the voltage between terminals 1 and 6 for each fuel
level.
HINT:
The fuel sender gauge cannot be removed.
As the resistance value changes according to the remaining
fuel amount, refer to the above standard value.
Fuel levelResistance (W)
FullApprox. 430
HalfApprox. 1000 ± 2000
EmptyApprox. 5000
If resistance value is not as specified, replace the fuel tank.
If resistance value is as specified, replace the combination me-
ter.
6. INSPECT TEMPERATURE SENDER RESISTANCE
Measure the resistance between terminal 4 and 8
If the resistance value is not in the following area, replace fuel
tank.
1.5 ± 100 (W) at 0 ± 30°C
7. INSPECT LOW OIL PRESSURE WARNING LIGHT
(a) Disconnect the connector from the warning switch and
ground terminal of the wire harness side connector.
(b) Turn the ignition switch ON, check that the warning light
lights up.
If the warning light does not light up, test the bulb or inspect wire
harness.
8. INSPECT LOW OIL PRESSURE SWITCH CONTINUITY
(a) Check that continuity exists between terminal and ground
with the engine stopped.
(b) Check that no continuity exists between terminal and
ground with the engine running.
HINT:
Oil pressure should be over 24.5 kPa (0.25 kgf/cm
2, 3.55 psi)
If operation is not as specified, replace the switch.
Page 1906 of 1943

AC2810
AC0Y9±05
AC2811
N11084
Wrong Okay
HI LO HILO
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±1
1889 Author: Date:
2001 PRIUS (RM778U)
AIR CONDITIONING SYSTEM
PRECAUTION
1. DO NOT HANDLE REFRIGERANT IN AN ENCLOSED
AREA OR WEAR A NAKED FLAME
2. ALWAYS WEAR EYE PROTECTION
3. BE CAREFUL NOT TO GET LIQUID REFRIGERANT IN
YOUR EYES OR ON YOUR SKIN
If liquid refrigerant gets in your eyes or on your skin.
(a) Wash the area with lots of cool water.
CAUTION:
Do not rub your eyes or skin.
(b) Apply clean petroleum jelly to the skin.
(c) Go immediately to a physician or hospital for professional
treatment.
4. NEVER HEAT CONTAINER OR EXPOSE IT TO NAKED
FLAME
5. BE CAREFUL NOT TO DROP CONTAINER AND NOT
TO APPLY PHYSICAL SHOCKS TO IT
6. DO NOT OPERATE COMPRESSOR WITHOUT
ENOUGH REFRIGERANT IN REFRIGERATION SYS-
TEM
If there is not enough refrigerant in the refrigerant system oil lu-
brication will be insufficient and compressor burnout may occur,
so that care to avoid this, necessary care should be taken.
7. DO NOT OPEN PRESSURE MANIFOLD VALVE WHILE
COMPRESSOR IS OPERATE
If the high pressure valve is opened, refrigerant flows in the re-
verse direction and could cause the charging cylinder to rup-
ture, so open and close the only low pressure valve.
8. BE CAREFUL NOT TO OVERCHARGE SYSTEM WITH
REFRIGERANT
If refrigerant is overcharged, it causes problems such as insuffi-
cient cooling, poor fuel economy, engine overheating etc.
Page 1912 of 1943

I01390
Condition: Insufficient cooling
I01392
Condition: Insufficient cooling
NOTE : These gauge indica-
tions are shown when the
refrigeration system has
been opened and the refrig-
erant charged without vacu-
um purging.
± AIR CONDITIONINGAIR CONDITIONING SYSTEM
AC±7
2001 PRIUS (RM778U)
(6) Refrigerant overcharged or insufficient cooling of
condenser
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
No air bubbles seen through the
sight glass even when the engine
rpm is lowered Unable to develop sufficient per-
formance due to excessive refrig-
eration system
Insufficient cooling of condenser Excessive refrigerant in
cycle " refrigerant over charged
Condenser cooling " condenser
fins clogged of condenser fan
faulty
(1) Clean condenser
(2) Check condenser fan motor
operation
(3) If (1) and (2) are in normal
state, check amount of refrigerant
Charge proper amount of refriger-
ant
(7) Air present in refrigeration system
Symptom seen in
refrigeration systemProbable causeDiagnosisRemedy
Pressure too high on both low
and high pressure sides
The low pressure piping hot to
touch
Bubbles seen in sight glass
Air entered in refrigeration system
Air present in refrigeration sys-
tem
Insufficient vacuum purging
(1) Check compressor oil to see if
it is dirty or insufficient
(2) Evacuate air and charge new
refrigerant