Page 8 of 1943

2001 PRIUS (EWD414U)
B HOW TO USE THIS MANUAL
The ground points circuit diagram shows the connections from all major parts to the respective ground points. When
troubleshooting a faulty ground point, checking the system circuits which use a common ground may help you identify
the problem ground quickly. The relationship between ground points (
EA, IB and IC shown below) can also be
checked this way.
I GROUND POINT
FAN MAIN RELAY
FAN MAIN RELAY
A/C FAN RELAY NO.2
A/C FAN RELAY NO.3
RADIATOR FAN MOTOR
RETRACT CONTROL
RELAY
RETRACT MOTOR RH
RETRACT MOTOR LH
FRONT TURN SIGNAL
LIGHT RH
PARKING LIGHT RH
FRONT TURN SIGNAL
LIGHT LH
PARKING LIGHT LH
DOOR LOCK CONTROL
SW RH
DOOR KEY LOCK
SW RH
DOOR LOCK MOTOR
RH
BLOWER RESISTOR
A/C AMPLIFIER
RADIO AND PLAYER
HEATER RELAY
AUTO ANTENNA
MOTOR
BLOWER SW
PARKING BRAKE SW
COMBINATION METER
HORN SW [COMB. SW]
TURN SIGNAL FLASHER
DOOR KEY LOCK SW LH
DOOR LOCK MOTOR LH
FUEL CONTROL SW
WOOFER AMPLIFIER
COMBINATION METER
COMBINATION METER
FUEL SENDER
CIGARETTE LIGHTER
O/D MAIN SW
CLOCK
5
5
5
5
4
4
4
4
4BA15
IB18
EA2 10
3E5
3E
6 3G
13 3F
3 3D
1 3B
7
ID115
IC33
IA12
E 3
A
A AW±B
W±BW±B W±B
W±B W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±BW±B W±B W±B W±B
W±B W±B
W±BW±B
W±B
W±B
W±B W±B
W±B
BR
W±B
BR BRW±BW±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B
W±B W±B
W±B
W±B
W±B
W±B
BR W±B
BR BR
BR W±B W±BW±B
W±BW±BBR W±B (4A±GZE)
W±B A A A
I 6
I 6
I 2
I 2
I 2
B 5I 5
I 5
I 5
B 5
B 5
B 5
I 5
I 5
I 3I 3
E 3
E 3
E 3
E 2
E 4
E 5
E 4
E 5
E 6E 4
E 4
B 4
EAI 4
B 4
B 4
I 4I 8
IBIC
3C7
4
JUNCTION
CONNECTOR J 1
4
DOOR LOCK CONTROL
RELAY
ELECTRICAL IDLE-UP
CUT RELAY (M/T)FRONT SIDE MARKER
LIGHT RH
FRONT SIDE MARKER
LIGHT LH
BRAKE FLUID LEVEL
WARNING SW
UNLOCK WARNING
SW WIPER AND WASHER
SW [COMB. SW] LIGHT CONTROL SW
[COMB. SW] HEATER CONTROL
ASSEMBLY
HEATER SERVO
MOTOR AMPLIFIER
DIMMER SW
[COMB. SW]
CRUISE CONTROL
MIRROR SW
REAR WINDOW
DEFOGGER SW
POWER WINDOW
MASTER SW
POWER WINDOW
CONTROL RELAY
DOOR LOCK CONTROL
SW
REMOTE CONTROL
MIRROR SW
*The system shown here is an EXAMPLE ONLY. It is different to the actual circuit shown in the SYSTEM CIRCUITS SECTION.
Page 37 of 1943

2001 PRIUS (EWD414U)
G
Position of Parts in Instrument Panel
G 1 Gateway ECU
H 7 Hazard Warning SW
H 8 Hazard Warning SW
H 9 Heated Oxygen Sensor (Bank 1 Sensor 2)
H 10 Hybrid Vehicle Control ECU
H 11 Hybrid Vehicle Control ECU
H 12 Hybrid Vehicle Control ECU
H 13 Hybrid Vehicle Control ECU
H 14 Hybrid Vehicle Control ECU
I 15 Ignition SW
J 1 Junction Connector
J 2 Junction Connector
J 3 Junction Connector
J 4 Junction Connector
J 5 Junction Connector
J 6 Junction Connector
J 7 Junction Connector
J 8 Junction Connector
J 9 Junction Connector
J 10 Junction Connector
J 11 Junction Connector
J 12 Junction Connector
J 13 Junction Connector
J 14 Junction Connector
J 15 Junction Connector
J 16 Junction Connector
J 17 Junction Connector
J 18 Junction Connector
J 19 Junction Connector
J 20 Junction Connector
J 21 Junction ConnectorJ 22 Junction Connector
J 23 Junction Connector
J 24 Junction Connector
J 25 Junction Connector
J 26 Junction Connector
J 27 Junction Connector
J 28 Junction Connector
J 29 Junction Connector
L 1 Light Control Rheostat
M 5 Multi Display
M 6 Multi Display
M 7 Multi Display
P 1 Park/Neutral Position SW
P 2 Parking Brake SW
P 3 PTC Heater
P 4 PTC Heater
R 2 Radio and Player
R 3 Radio and Player
R 4 Radio and Player
R 5 Remote Control Mirror SW
S 2 Shift Lock ECU
S 3 Stop Light SW
T 4 Transponder Key Computer
T 5 Turn Signal Flasher Relay
U 1 Unlock Warning SW and Key Interlock Solenoid
W 5 Wireless Door Control Receiver
Page 76 of 1943

2001 PRIUS (EWD414U)
HYBRID VEHICLE IMMOBILISER SYSTEM
7. 5A
ECU±B FROM POWER SOURCE SYSTEM (
SEE PAGE 50)
2C 5
A A AA F
B H
5JUNCTION
CONNECTOR J20
JUNCTION
CONNECTOR J11 1
12
R±G R±G R±G LG±B
W±B W± B W±B
+B HEVC
IND
JUNCTION
CONNECTORB J27 A , J28
ID2 10 ID2 11 76
15A
AM2
1B 21J 92C 2
2G 1
D 1C 1
120A MAIN
1AM2 IG2
ST2
IFC 8
B 7B E
A A
JUNCTION
CONNECTORB J27 A , J28
JUNCTION
CONNECTORB J27 A , J28
B F
A D
JUNCTION
CONNECTORB J12 A , J13
B D
A B
JUNCTION
CONNECTORB J27 A , J28
A A
B A
JUNCTION
CONNECTORB J24 A , J25
ID A A
2D 8
1 2ID1 9B B
IB1 3
1 ID2 8
JUNCTION
CONNECTOR J10
JUNCTION
CONNECTOR J20
46711 7
238
6DATA LINK
CONNECTOR 3 D 2
HYBRID VEHICLE
CONTROL ECU H14
CENTER
CLUSTER SW C 7
DOOR COURTESY
SW FRONT LH D 6
UNLOCK WARNING SW U 1RADIO AND PLAYERC R 3 B , R 4FUSIBLE LINK
BLOCK NO. 1D F1 2 C , F13 BATTERYB±G B W±R W±R
B±W B±W B±W
B±R
B±WB±R R±W
L±B
W±BL±B L±B L±B
W±BR±W R±WLG±B BR BR
LG±B
2K 8
A IG D
KSW CTY
LG±B
FUSIBLE LINK
BLOCK NO. 2 F18
W±B
W± B ID1 8
R±G
IGNITION SW I15
OP1 FC VC
GND
TRANSPONDER KEY
COMPUTER T 4 A C
A CJUNCTION
CONNECTORJ24 A
Page 91 of 1943
2001 PRIUS (EWD414U)
A H
B FBFBFBF
2 5
105
A 5B 10
ID 2K 82D 8
B D
A EB 6B7 A H A H
4
AC
B
B
EA CCC
EA A635
A
B
A
LG LG LG LG W±L
W±L
W±L
W±L
W± B
W± L W±B W±B W±BW± L
W± L
W± LW± L
W±B
W± LLG±R
W±B
W±B W± LFROM POWER SOURCE SYSTEM (
SEE PAGE 50)
HAZARD WARNING SW H 7
CENTER CLUSTER SW C 7
LIGHT CONTROL
RHEOSTAT L 1 JUNCTION
CONNECTOR J21
JUNCTION
CONNECTOR J24
JUNCTION
CONNECTOR J11
JUNCTION
CONNECTOR J21
JUNCTION
CONNECTOR J21
RADIO AND PLAYERB R 2 A , R 3
JUNCTION
CONNECTORB J22 A , J23
JUNCTION
CONNECTORB J27 , J28A
W±LJUNCTION
CONNECTOR J21
LG LG LG
A H
A 2115A
DOME
1J 7
2G 2
2A 4
L±Y L
LG
W±L
W±L
LG
LG
LG
CE TC ILL±T
COMBINATION METERB C10 A , C11
A 14
IH 2B 62A 7
BRL
Page 147 of 1943
2001 PRIUS (EWD414U)
B 14 B15
IN1 1IN16
IQ1 2 65
3 L1 UL1
W±B
R±B G±B
W± BG± B
R±B
BODY ECUB B 8 , B 9A
UNLOCKLOCK
D10
DOOR LOCK
CONTROL SW
FRONT RH10A
HORN FROM POWER SOURCE SYSTEM (
SEE PAGE 50)
23 15
1J 2 A 10
ID2 4IA28 A 20 A13 B13
IE1 9IE110
1
2 1
IE IFB 7C 84
AA
D D A
A
A6 SH HCTY IND HR
B±W B±W
R±W
LG±BR±W
LG±B
B±R B±R
B±R B±R B±R BR W± B W±B
BRTHEFT DETERRENT
HORN T 1
ENGINE HOOD
COURTESY SW E 2
CENTER CLUSTER SW C 7JUNCTION
CONNECTOR J27
JUNCTION
CONNECTOR J20
HORN
RELAY
JUNCTION
CONNECTOR J 7
JUNCTION
CONNECTOR J 1RADIO AND
PLAYERC R 3 , R 4B
Page 150 of 1943
2001 PRIUS (EWD414U)
RADIO AND PLAYER
12 IG1 3IG14 B 2B6
2 1 IN1 3IN14 B 1B5
2 1 A 2A6
2 1 A 1A3 15A
DOMEFROM POWER SOURCE SYSTEM (
SEE PAGE 50)
1J 710A
ACC
2D 2
B 3 B 46B B 2IJ2 9 IJ2 8
L±Y
GR ±R
P
V V P GR± RL±Y
P
V
LG
L
B
Y
R
W P
V
LG
L
B
Y
R
W
AUI+ AUI±
110NAVIGATION
ECU N 2
FRONT DOOR
SPEAKER LH F14
FRONT DOOR
SPEAKER RH F15
REAR SPEAKER
LH R 8
REAR SPEAKER
RH R 9 2G 2
2D 4
L±Y
2 1 IG1 3IG14 AUO+ AUO±
G
R P
V
FRONT DOOR
SPEAKER LH F14 IJ2 6IJ27
G
R
211
(
*1)
(
*1) (
*1) (
*1) (
*1)
(
*1)(
*1) (
*1) (
*1)
(
*1) (
*2)
(
*2) (
*2)
(
*2)
B C A CACIJ1 1IJ14
JUNCTION
CONNECTOR J24JUNCTION
CONNECTORB J27 A , J28
BBB+B ACC
L±Y
L±Y
GR ±R GR±R
918
B
B
GR ±R
JUNCTION
CONNECTOR J26
17BR
GND
RADIO AND PLAYERB R 2 , R 3A
IF1 7IF18IF15IF16 C , R 4 BU+B ACC+B FL+ FL±
FL+ FL± FR+ FR± RL+ RL± RR+ RR±
Page 151 of 1943
2001 PRIUS (EWD414U)
C 10 C9
B 7 C 8
IF
R
G
G
R
BR BRGR
BR BR
TX± TX+ GND
310 874
CF CF
F
C MULTI
DISPLAY M 5
CENTER CLUSTER SW C 7
JUNCTION
CONNECTOR J26
IJ1 21 BR
BR BR
* 1 : W/ NAVIGATION SYSTEM
* 2 : W/O NAVIGATION SYSTEM
RADIO AND PLAYERB R 2 , R 3AC, R 4 G
R
12 C
GR GR
ACC
1
11 C
P±B P±B
EJCT
9
5C
L±R L±R
+B
2
GND TX+ TX± GND ACC+B EJECT BU+B TX+ TX±
Page 152 of 1943

2001 PRIUS (EWD414U)
RADIO AND PLAYER
R3 (B) RADIO AND PLAYER
(B)4±GROUND : Always approx. 12 volts
(B)3±GROUND : Approx. 12 volts with the ignition SW at ON or ACC position
(B)7±GROUND : Always continuity
N2 NAVIGATION ECU
9±GROUND : Always approx. 12 volts
18±GROUND : Approx. 12 volts with the ignition SW at ON or ACC position
17±GROUND : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
C736J27A37R3B37
F1438J28B37R4C37
F1538M537R839
J2437N239R939
J2637R2A37
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
1J27Engine Room Main Wire and Engine Room J/B (Engine Compartment Left)
2D30Instrument Panel Wire and Instrument Panel J/B (Cowl Side Panel LH)
2G31Engine Room Main Wire and Instrument Panel J/B (Cowl Side Panel LH)
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CodeSee PageJoining Wire Harness and Wire Harness (Connector Location)
IF142Instrument Panel Wire and Floor Wire (Left Kick Panel)
IG142Front Door LH Wire and Instrument Panel Wire (Left Kick Panel)
IJ144Floor No 3 Wire and Instrument Panel Wire (Under the Instrument Panel Center)IJ244Floor No.3 Wire and Instrument Panel Wire (Under the Instrument Panel Center)
IN144Front Door RH Wire and Instrument Panel Wire (Right Kick Panel)
: GROUND POINTS
CodeSee PageGround Points Location
IF42Left Kick Panel
SERVICE HINTS