2001 TOYOTA PRIUS fuse diagram

F12823
ECU±IG Fuse
Instrument Panel J/B
DI±482
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check ECU±IG fuse.
PREPARATION:
Remove the ECU±IG fuse from the instrument panel J/B.
CHECK:
Check the continuity of the ECU±IG.
OK:
Continuity
NG Check for short circuit in all harness and com-
ponents connected to ECU±IG fuse (See at-
tached wiring diagram).
OK
2 Check that the battery positive voltage when IG switch is OFF.
OK:
Voltage: 9 ± 14 V
NG Charge or replace the battery.
OK

F12862
Engine Room
R/B No. 3
EMPS
Fuse
DI±486
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
2001 PRIUS (RM778U)
3 Check EMPS fuse.
PREPARATION:
5/18/01Remove the EMPS fuse from engine room R/B No. 3.
CHECK:
5/18/01Check continuity of EMPS fuse.
OK:
Continuity
NG Check for short circuit in harness and all com-
ponents connected to EMPS fuse (See attached
wiring diagram).
OK
Check for open and short circuit in harness and connector between EMPS ECU and battery
(See page IN±41).

F12863
Instrument
Panel J/BECU±B
Fuse
DI±490
± DIAGNOSTICSELECTRIC MOTOR POWER STEERING
2001 PRIUS (RM778U)
NG Replace EMPS relay.
OK
3 Check ECU±B fuse.
PREPARATION:
Remove the ECU±B fuse from instrument panel J/B.
CHECK:
Check the continuity of ECU±B fuse.
OK:
Continuity
NG Check for short in harness and all components
connected to ECU±B fuse (See attached wiring
diagram).
OK
Check for open and short circuit in harness and connector between EMPS ECU and battery
(See page IN±41).

± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±659
2001 PRIUS (RM778U)
Power source circuit
CIRCUIT DESCRIPTION
This circuit provides power to operate the hybrid vehicle control ECU.
WIRING DIAGRAM
See page DI±156.
INSPECTION PROCEDURE
1 Check IGN and EFI fuse.
CHECK:
Check continuity of IGN and EFI fuse.
OK:
Continuity
NG Replace the failure fuse.
OK
2 Check voltage between terminals IGSW, BATT and GND of hybrid vehicle control
ECU connector (See page IN±41).
PREPARATION:
(a) Turn ignition switch OFF.
(b) Disconnect the hybrid vehicle control ECU connector.
CHECK:
Measure voltage between terminals IGSW, BATT and GND
OK:
Voltage: 10 ± 14 V
OK Proceed to next circuit inspection shown in
problem symptoms table (See page DI±648).
NG
DI7NJ±01

I18396
Engine Room R/B No. 3
HTR3 Fuse
Z18060
15 2
3
123 5
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±945
2001 PRIUS (RM778U)
3 Check HTR3 fuses.
PREPARATION:
Remove the HTR3 fuse from engine room R/B No. 3.
CHECK:
Check continuity of HTR1 and HTR2 fuses.
OK:
Continuity exists.
NG Check for short in all the harness and compo-
nents connected to the HTR1 and HTR2 fuses
(See attached wiring diagram).
OK
4 Check HTR3 relays.
PREPARATION:
Remove the HTR3 relays from engine room relay block No. 3.
CHECK:
Check continuity between each pair of terminals shown below
of magnetic clutch relay.
OK:
Tester connectionSpecified condition
1 ± 262.5 ± 90.9 W
3 ± 5No continuity
PREPARATION:
Apply battery positive (+) voltage between terminals 1 and 2.
CHECK:
Check continuity between terminals 3 and 5.
OK:
Continuity exists.
NG Replace HTR3 relay.
OK

I18396
Engine Room R/B No. 3
HTR1 Fuse HTR2 Fuse
Z18060
15 2
3
123 5
DI±950
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2001 PRIUS (RM778U)
3 Check HTR1 and HTR2 fuses.
PREPARATION:
Remove the HTR1 and HTR2 fuses from engine room R/B NO.
3.
CHECK:
Check continuity of HTR1 and HTR2 fuses.
OK:
Continuity exists.
NG Check for short in all the harness and compo-
nents connected to the HTR1 and HTR2 fuses
(See attached wiring diagram).
OK
4 Check HTR1 and HTR2 relays.
PREPARATION:
Remove the HTR1 and HTR2 relays from engine room relay
block NO. 3.
CHECK:
Check continuity between each pair of terminals shown below
of magnetic clutch relay.
OK:
Tester connectionSpecified condition
1 ± 262.5 ± 90.9 W
3 ± 5No continuity
PREPARATION:
Apply battery positive (+) voltage between terminals 1 and 2.
CHECK:
Check continuity between terminals 3 and 5.
OK:
Continuity exists.
NG Replace HTR1 and (or) HTR2 relay.
OK

I18401
A/C Amplifier
CF Engine Room J/B
Fan No.2 Relay
A9
A91
2RF IE16
R±W R±W
1J
1A
1J
1K
1J
1K
1B
1J
1K 1K 10
11
5
3
12
5
2
3
4
7 Fan No.1 Relay
Fan No.1 Relay1
2
5 3
4
1
2
5
3
3 5
12
CDS FAN
RDIV±YJ27
J28J27 EE
E J/C L±W To Engine ECU
W±B
V±Y
From
DC/DC Fuse
From ECU±
IG Fuse 1
1 2 R1 Radiator Fan Motor
W4 Water Temp. Switch12
W±B
W±BA3 A/C Pressure Switch2 3
J1
J/CJ7
J/C
AA A
AW±BW±B
IEV±Y
A1
A/C Condenser
Fan Motor
G±W
W±G
W
L±W2
W±B W±B
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±953
2001 PRIUS (RM778U)
WIRING DIAGRAM

I18394
Engine Room J/B
CDS Fuse
RDI Fuse
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±955
2001 PRIUS (RM778U)
3 Check RDI fuse and CDS fuse.
PREPARATION:
Remove RDI fuse and CDS fuse from engine room J/B.
CHECK:
Check continuity of RDI fuse and CDS fuse.
OK:
Continuity exists.
NG Check for short in all the harness and compo-
nents connected to the RDI fuse (See attached
wiring diagram).
OK
Check harness and connector between A/C control amplifier and battery (See page IN±41).
4 Check fan motor operation (See page AC±67).
NG Replace fan motor.
OK
5 Check pressure switch (See page AC±62).
NG Replace pressure switch.
OK