Page 9 of 1943

2001 PRIUS (EWD414U)
B
The ºCurrent Flow Chartº section, describes which parts each power source (fuses, fusible links, and circuit breakers)
transmits current to. In the Power Source circuit diagram, the conditions when battery power is supplied to each system
are explained. Since all System Circuit diagrams start from the power source, the power source system must be fully
understood.
Theft Deterrent and Door Lock Control
J POWER SOURCE (Current Flow Chart)
11
1
EA1 1EA2 3
7
EB16
E 6
E 7I 2I 2
I 2
E 7
E 7
E 7
2
1
1
2
2
2
2
2
B
B
W W
B B B B BW±B
B
B
B B±O
B±W
W±B
B±W STARTER RELAY INJECTION RELAY15A HAZ±RADIO7.5A AM250A MAIN 1.25B FL MAIN
BATTERY
WWW
W W W
R W±L
W
W
G±W
G
15A TAIL
20A DEFOG
15A RAD CIGTA I L
RELAY 7.5A DOME 40A DOOR LOCK CB
2 1
1 2
4 8
2 3
3 4
G
W±R
P±L B±Y
B±Y
W±R
AM2 IG2
ACC
IG1AM1W W
W±R
W W
W±B
21
1
1
1
1
2
2
2
2
3
4
3
4 1
2
1
22
1
11
1
IGNITION SW I 8
Battery
30A AM2
2
Starter S 220A RADIO NO.1
10A HORN
15A EFI
7.5A DOMEShort Pin
10A HAZARD
The chart below shows the route by which current flows from the battery to each electrical source
(Fusible Link, Circuit Breaker, Fuse, etc.) and other parts.
Engine Room R/B (See Page 20)
ABS
ABS and Traction Control
Cruise Control
Electronically Controlled Transmission and A/T Indicator
Multiplex Communication System
Cigarette Lighter and Clock
Key Reminder and Seat Belt Warning STOP
Fuse Page
194
214
11 2
System
DOME 20A
10ACombination Meter
Headlight
Interior Light
2
2
6 100A ALT
EB1
POWER SOURCE
Light Auto Turn Off187
180
166
210
230
122
10A ECU±B
5 60A ABS
2
6 Fusible Link Block2
*The system shown here is an EXAMPLE ONLY. It is different to the actual circuit shown in the SYSTEM CIRCUITS SECTION.
Page 202 of 1943

2001 PRIUS (EWD414U)
J POWER SOURCE (Current Flow Chart)
Fusible Link Block No.1 (See Page 22)
FuseSystemPage
100ADC/DC
Illumination
Key Reminder and Light Reminder Buzzer
Light Auto Turn Off
Taillight
TOYOTA Hybrid System92
11 4
104
88
54
Fusible Link Block No.2 (See Page 23)
FuseSystemPage
5ADC/DC±STOYOTA Hybrid System54
120AMAIN
ABS
Engine Control
Headlight (w/o Daytime Running Light)
Hybrid Vehicle Immobiliser System
Illumination
Key Reminder and Light Reminder Buzzer
Light Auto Turn Off
SRS
Taillight
TOYOTA Hybrid System172
68
84
78
92
11 4
104
167
88
54
Engine Room R/B No.3 (See Page 24)
FuseSystemPage
7.5ADRLHeadlight (w/ Daytime Running Light)80
10AABS NO.4ABS172
30AHTR1Air Conditioning188
30AHTR2Air Conditioning188
40AABS NO.1ABS172
50AEMPSEMPS164
50AHTR3Air Conditioning188
Engine Room J/B (See Page 26)
FuseSystemPage
10ABATT FANTOYOTA Hybrid System54
10AHEAD (LH)Headlight (w/o Daytime Running Light)84
10AHEAD (RH)Headlight (w/o Daytime Running Light)84
10AHEAD HI (LH)Headlight (w/ Daytime Running Light)80
10AHEAD HI (RH)Headlight (w/ Daytime Running Light)80
10AHEAD LO (LH)Headlight (w/ Daytime Running Light)80
10AHEAD LO (RH)Headlight (w/ Daytime Running Light)80
10AHORNHorn
Theft Deterrent124
146
10ATURN±HAZTurn Signal and Hazard Warning Light96
*These are the page numbers of the first page on which the related system is shown.
Page 203 of 1943

2001 PRIUS (EWD414U)
J
FuseSystemPage
15AAM2
ABS
Engine Control
Hybrid Vehicle Immobiliser System
SRS
TOYOTA Hybrid System172
68
78
167
54
15ADOME
Combination Meter
Door Lock Control
Headlight (w/ Daytime Running Light)
Headlight (w//o Daytime Running Light)
Illumination
Interior Light
Key Reminder and Light Reminder Buzzer
Navigation System
Power Window
Radio and Player
Seat Belt Warning
Theft Deterrent
TOYOTA Hybrid System
Wireless Door Lock Control182
134
80
84
92
108
11 4
156
126
152
11 8
146
54
140
15AEFIEngine Control68
15ATHROEngine Control68
20AABS NO.3ABS172
20AHVTOYOTA Hybrid System54
30AABS NO.2ABS172
30ACDS FANRadiator Fan and Condenser Fan186
30AHEAD
Headlight (w/ Daytime Running Light)
Key Reminder and Light Reminder Buzzer
Light Auto Turn Off80
11 4
104
30ARDIRadiator Fan and Condenser Fan186
50AHTRAir Conditioning188
Instrument Panel J/B (See Page 30)
FuseSystemPage
5AECU±IG
ABS
Electric Tension Reducer
EMPS
Gateway System
Navigation System
Radiator Fan and Condenser Fan
Shift Lock172
162
164
160
156
186
132
5APANELIllumination92
7.5AECU±BAir Conditioning
Combination Meter188
182
*These are the page numbers of the first page on which the related system is shown.
Page 204 of 1943

2001 PRIUS (EWD414U)
J POWER SOURCE (Current Flow Chart)
FuseSystemPage
7.5AECU±B
Door Lock Control
EMPS
Gateway System
Headlight (w/ Daytime Running Light)
Hybrid Vehicle Immobiliser System
Interior Light
Key Reminder and Light Reminder Buzzer
Light Auto Turn Off
Power Window
Theft Deterrent
Wireless Door Lock Control134
164
160
80
78
108
11 4
104
126
146
140
7.5AOBDIIEngine Control
Theft Deterrent68
146
7.5ATAIL
Key Reminder and Light Reminder Buzzer
Light Auto Turn Off
Taillight11 4
104
88
10AACC
Combination Meter
Gateway System
Navigation System
Radio and Player
Remote Control Mirror
Shift Lock
SRS182
160
156
152
130
132
167
10AGAUGE
ABS
Air Conditioning
Back±Up Light
Combination Meter
Door Lock Control
EMPS
Engine Control
Headlight (w/ Daytime Running Light)
Key Reminder and Light Reminder Buzzer
Light Auto Turn Off
Navigation System
Power Window
Rear Window Defogger
Seat Belt Warning
Theft Deterrent
TOYOTA Hybrid System
Turn Signal and Hazard Warning Light
Wireless Door Lock Control172
188
102
182
134
164
68
80
11 4
104
156
126
180
11 8
146
54
96
140
10AHTRAir Conditioning188
10ASRS ACCSRS167
*These are the page numbers of the first page on which the related system is shown.
Page 205 of 1943
2001 PRIUS (EWD414U)
J
FuseSystemPage
15ACIGCigarette Lighter122
15ASTOP
ABS
Engine Control
Shift Lock
Stop Light172
68
132
100
15AWASHERWiper and Washer120
20APWR1Power Window126
30ADOOR
Door Lock Control
Theft Deterrent
Wireless Door Lock Control134
146
140
30APOWERPower Window126
30AWIPERWiper and Washer120
40ADEFRear Window Defogger180
*These are the page numbers of the first page on which the related system is shown.
Page 458 of 1943
BE1367
Medium Current Fuse and High Current Fuse
Equal Amperage Rating
V00076
Abbreviation Part Name Symbol Illustration
FUSE
MEDIUM CURRENT FUSE
HIGH CURRENT FUSE
FUSIBLE LINK
CIRCUIT BREAKERFUSE
M±FUSE
H±FUSE
FL
CB
± INTRODUCTIONREPAIR INSTRUCTIONS
IN±5
5 Author: Date:
2001 PRIUS (RM778U)
(3) Precoated parts are indicated in the component il-
lustrations by the ºº symbol.
(g) When necessary, use a sealer on gaskets to prevent
leaks.
(h) Carefully observe all specifications for bolt tightening
torques. Always use a torque wrench.
(i) Use of special service tools (SST) and special service ma-
terials (SSM) may be required, depending on the nature
of the repair. Be sure to use SST and SSM where speci-
fied and follow the proper work procedure. A list of SST
and SSM can be found in Preparation section in this
manual.
(j) When replacing fuses, be sure the new fuse has the cor-
rect amperage rating. DO NOT exceed the rating or use
one with a lower rating.
Page 775 of 1943

A04550
DLC3
912 3 4 56 78
16 15 14 13 12 11 10
DI±178
± DIAGNOSTICSHYBRID VEHICLE CONTROL SYSTEM
2001 PRIUS (RM778U)
Freeze frame data:
As the freeze frame data records the driving condi-
tion when a malfunction is detected, when trouble-
shooting, it is useful for determining whether the ve-
hicle was running, braked, stopped or reversed.
(b) Check the DLC3.
The HV control ECU conforms to ISO 14230 for commu-
nication.
The terminal arrangement of the DLC3 complies with
SAEJ1962 and matches the ISO 14230 format.
Terminal No.Connection/Voltage or ResistanceCondition
7Bus Line/Pulse generationDuring transmission
4Chassis Ground e Body Ground/1 W or lessAlways
5Signal Ground e Body Ground/1 W or lessAlways
16Battery Positive e Body Ground/10 ± 15 VAlways
HINT:
If your display shows UNABLE TO CONNECT TO VEHICLE
when you have connected the cable of the TOYOTA hand±held
tester to the DLC3, turned the motor switch ON and operated
the tester, there is a problem in the vehicle or tool.
If communication is normal when the tool is connected to
another vehicle, inspect the DLC3 on the original vehicle.
If communication is still not possible when the tool is con-
nected to another vehicle, the problem is probably in the
tool itself, so consult the Service Department.
3. INSPECT DIAGNOSIS
(a) Check the auxiliary battery.
(1) Measure the voltage of the auxiliary battery.
Voltage: 10 ± 15 V
(2) Inspect the auxiliary battery, fuses, fusible links, wir-
ing harness, connectors and ground.
Page 907 of 1943

A14089
B12009
F12396
DLC3
TOYOTA hand±held tester
± DIAGNOSTICSHV BATTERY CONTROL SYSTEM
DI±317
2001 PRIUS (RM778U)
(2) Inspect the auxiliary battery, fuses, fusible links, wir-
ing harness, connectors and ground.
(b) Check the master warning light.
(1) Turn the ignition switch ON and confirm that the
master warning light comes on.
HINT:
If the master warning light does not come on, suspect a burnt
fuse, burnt bulb, or open in wiring harness.
(2) When the ºREADYº light is ON, the master warning
light should go off.
If the lamp remains on, the diagnosis system has detected a
malfunction or abnormality in the system.
(c) Check the DTC.
(1) Prepare a TOYOTA hand±held tester.
(2) Connect the TOYOTA hand±held tester to the
DLC3.
(3) Turn the ignition switch ON and push the TOYOTA
hand±held tester main switch ON.
(4) Use the TOYOTA hand±held tester to check the
DTC and freeze frame data and note them down.
(For operating instructions, see the TOYOTA hand±
held tester operator's manual).
Since the HV battery ECU stores DTC and freeze
frame data, when troubleshooting, check all of the
DTC, write down the freeze fame data and perform
inspection according to the procedures of ºCircuit
Inspectionº.
Because the HV battery ECU is communicating with
the HV ECU, if any DTC is stored in the HV battery
ECU, check and record DTC stored in the HV ECU
(For tables for DTC, see page DI±177).
(5) See a related page to confirm details of the DTC.