Page 175 of 1943

2001 PRIUS (EWD414U)
1. INPUT SIGNALS
(1) Speed sensor signal
The speed of the wheels is detected and input to TERMINALS FL+, FR+, RL+ and RR+ of the brake ECU.
(2) Stop light SW signal
A signal is input to TERMINAL STP of the brake ECU when the brake pedal is depressed.
2. ABS SYSTEM OPERATION
During sudden braking the brake ECU has signals input from each sensor, which controls the current to the solenoid inside
the actuator and lets the hydraulic pressure acting on each wheel cylinder escape to the reservoir. The pump inside the
actuator is also operating at this time and it returns the brake fluid from the reservoir to the master cylinder, thus preventing
locking of the vehicle wheels.
If the brake ECU judges that the hydraulic pressure acting on the wheel cylinder is insufficient, the current on the solenoid is
controlled and the hydraulic pressure is increased. Holding of the hydraulic pressure is also controlled by the brake ECU, by
the same method as above. Pressure reduction, holding and increase are repeated to maintain vehicle stability and to
improve steerability during sudden braking.
A4, A5 ABS SPEED SENSOR FRONT LH, RH
2±1 :1.4±1.8 kW (20°C, 68°F)
A23, A24 ABS SPEED SENSOR REAR LH, RH
2±1 :1.04±1.3 kW (20°C, 68°F)
B10 (A), B11 (B), B12 (C), B13 (D) BRAKE ECU
(B) 6, (C) 1±GROUND : Approx. 12 volts with the ignition SW at ON position
(D) 22±GROUND : Always approx. 12 volts
(A) 6, (A)31±GROUND : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A434C10A36J1037
A534C11B36J1137
A736D236J1237
A2338E636J14A37
A2438E1036J15B37
B1A34F12C34J1637
B2B34F13D34J1737
B3C34F1838J18A37
B434G137J19B37
B8A36H5A34J2237
B10A36H6B34J2637
B11B36H1538P237
B12C36I1537S337
B13D36J137
B1436J737
: RELAY BLOCKS
CodeSee PageRelay Blocks (Relay Block Location)
223Engine Room R/B No.2 (Right Side of Reserve Tank)
324Engine Room R/B No.3 (Engine Compartment Right)
SYSTEM OUTLINE
SERVICE HINTS
Page 180 of 1943
2001 PRIUS (EWD414U)
COMBINATION METER
VFD
A 22 A21 A20 A12 B2
A 14 A2A3A1B7B6B1A9A11 10A
GAUGE FROM POWER SOURCE SYSTEM (
SEE PAGE 50)
2A 515A
DOME
1J 7
2A 42G 2
IP1 4IP15 2J 62J82J9 7. 5A
ECU±B
2C 5B 9A 15 B 16
2B 62A 7
IH14
4 8
351516
13
GR±L
L L W±G LG±RW±LL L L L BR
GR GR±L
GR± BBR±RY±BY
L±WL±Y
L LR±G L±Y LLR±G R±G
MPX+ MPX± FU± FU+
MPX1 MPX2 BFUA
COMBINATION METERB C10 , C11A BODY ECUB B 8 , B 9A
FUEL SENDER F16
ENGINE CONTROL
MODULE E10
ODO/TRIP SW
[HAZARD WARNING SW] H 8FROM BACK±UP
LIGHT RELAY
FROM BRAKE ECU TO L IGHT
CONTROL RHEOSTAT
FROM EMPS ECUY
Y±B
BR±R L±Y
L±R
FUEL
SENDER
SENSOR 20 11 19
A F
A FJUNCTION
CONNECTORJ27 A
EODOTC
Page 182 of 1943
2001 PRIUS (EWD414U)
COMBINATION METER
MALFUNCTION
INDICATOR LAMP
ABS
SRS
TURN L
TURN R
HIGH BEAM OUTPUT CONTROLWAT ER TEMP.
(
HIGH) WAT ER TEMP.
(
LOW) CRUISE
A 17 A 18 A 19 B 5
A 16 A 10 B 4
L L L GR± R B±YL G±R
COMBINATION METERB C10 , C11A
FROM HEADLIGHTS (
*1)
FROM DAYTIME RUNNING
LIGHT RELAY (
*2) FROM TURN SI GNAL
FLASHER RELAY TO ENGINE
CONTROL MODULE
TO BRAKE ECU
TO AIRBAG SENSOR
ASSEMBLY
10A
ACC FROM POWER SOURCE SYSTEM (
SEE PAGE 50)
2D 2
GR± R
A B
B C
B B
JUNCTION
CONNECTOR J26
JUNCTION
CONNECTORB J27 , J28AGR ±R
GR± R* 1 : W/O DAYTIME RUNNING LIGHT
* 2 : W/ DAYTIME RUNNING LIGHT
Page 194 of 1943

2001 PRIUS (EWD414U)
I GROUND POINT
IGCT RELAY
A/C TRIPLE
PRESSURE SW
HYDRAULIC BOOSTER
WATER PUMP MOTOR
(
A/C)
FRONT PARKING
LIGHT LH
FRONT PARKING
LIGHT RHIG2 RELAY
ENGINE HOOD
COURTESY SW
FRONT WI PER MOTOR
FRONT TURN
SIGNAL LIGHT LH
RADIATOR FAN MOTOR
ABS SOL
RELAY
INVERTER
(
GND1)
(
GND2)
PTC HEATER
BLOWER MOTOR
LINEAR CONTROLLER
(
E1)
(
SG)
(
E01)
(
E02) FRONT SIDE MARKER
LIGHT LH
FRONT SIDE MARKER
LIGHT RH
FRONT TURN
SIGNAL LIGHT RH
BRAKE FLUID LEVEL
WARNING SW
WATER TEMP. SW
DRL RELAY
IGNITION COIL AND
IGNITER NO. 1
IGNITION COIL AND
IGNITER NO. 2
IGNITION COIL AND
IGNITER NO. 3
IGNITION COIL AND
IGNITER NO. 4
ENGINE CONTROL
MODULE1K3
E 5
E 5
E 5
E 5 E 5
E 5
E 5
E 5 (
±S)
E 5
E 5
3HYDRAULIC BOOSTER E 5 E 5 (
CUT±)
E 1
E 1
E 1
E 1
E 1
E 1
3W±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± 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 W±B W±B W±B W±B
W±B W±B W±B W±B W±B
A
AA
(
*1)IE ECW± B
W± B
W± B
W± B
W± B
W± B W±BA
AA
A
AJUNCTION
CONNECTOR J 7
J 1
JUNCTION
CONNECTOR
W±B
A
BRAKE ECU
EAE 3 E 3 E 3
EBID214
IO114 A A
B A JUNCTION
CONNECTORB J 8 , J 9A W±B
W±B
W±B
W±B
W±B
W±BBR
BR
W±B
W±BBR BR
W±B W±B W±B
BR
ENGINE CONTROL
MODULE
ENGINE CONTROL
MODULE
(
ME01)
(
E03)DATA LINK
CONNECTOR 3 HTR RELAY
NAVIGATION ECU
RADIO AND PLAYER
IFIJ121
BR
BR
BR BR
MULTI DISPLAY (
*2)(
*2)
AIRBAG SENSOR
ASSEMBLY
COMBINATION
METER(
E1)
(
ES)
IH W±B
2B6 7
LBR
2A WATER PUMP
MOTOR (
INVERTER)
2W±B
FAN NO. 2
RELAY
AEFI RELAY
Page 195 of 1943

2001 PRIUS (EWD414U)
HYBRID VEHICLE
CONTROL ECU
KEY INTERLOCK
SOLENOID
HAZARD WARNING
SW
BUCKLE SW AND
TENSION REDUCER LHPARK/NEUTRAL
POSITION SW
WIRELESS DOOR
CONTROL RECEIVER
(
GND)
(
CG)
CIGARETTE LIGHTER
DOOR LOCK MOTOR,
DOOR KEY LOCK AND
UNLOCK SW AND DOOR
UNLOCK DETECTION
SW FRONT LH
(
E)
IG1 RELAY
FUEL PUMP AND
FUEL SENDER
EMPS ECU
POWER WINDOW
CONTROL SW REAR RH
DOOR LOCK MOTOR AND
DOOR UNLOCK
DETECTION SW
REAR RH
POWER WINDOW
CONTROL SW FRONT RH
(
EL) A/C AMPLIFIER
UNLOCK
WARNING SW
REMOTE CONTROL SW
SHIFT LOCK ECU
BUCKLE SW RH AND
SEAT BELT WARNING
OCCUPANT DETECTION
SENSOR
AIRBAG SENSOR
ASSEMBLY
TRANSPONDER
KEY COMPUTER
POWER WINDOW
MASTER SW
PTC HEATER
DAYTIME RUNNING
LIGHT RELAY
BRAKE ECU* 1 : W/ DAYTIME RUNNING LIGHT
* 2 : W/ NAVIGATION SYSTEM
BB11
IQ11
IG ID B D
A E
E
A D
BE
A D
B
IJ111
B A
A A
B A
A A A
A A
B B A
A A
A
A A
B
A AIG12
IJ110
IC11
IA15
IA11 AA
A
A
A
AA
A AAA A A E
EW±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±BW±B
W±B
W±B
W±B
W±B
W±B W±B
W±B W± B
JUNCTION CONNECTORB J22 , J23A
JUNCTION
CONNECTORB J24 , J25A
2D8
2E3
2K8
A JUNCTION CONNECTOR J10
(
E)
(
E)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 J11
JUNCTION
CONNECTOR
J17
JUNCTION
CONNECTOR W±B
(
*1)
(
GND4) (
GND3)W± B
W± B
W± B
COMBINATION SW B 3W± B
W± B W±B
W±B
W±B
(
E)
(
CG) (
EOM)
(
KLS±)
GATEWAY ECU
DATA LINK
CONNECTOR 3
W±B
BODY ECU
(
E2) (
UN±) (
TL)LIGHT CONTROL
RHEOSTAT
GATEWAY ECU E
E
W± B E
JUNCTION
CONNECTOR J21
W±B
Page 196 of 1943
2001 PRIUS (EWD414U)
I GROUND POINT
REAR COMBINATION
LIGHT LH
LICENSE PLATE
LIGHT LH
HIGH MOUNTED
STOP LIGHT
REAR COMBINATION
LIGHT RH
LICENSE PLATE
LIGHT RH
SYSTEM MAIN RELAY
LUGGAGE COMPARTMENT
DOOR UNLOCK SWBATTERY MOTOR
BLOWER CONTROLLER
PERSONAL LIGHT
POWER WINDOW
CONTROL SW REAR LH
DOOR LOCK MOTOR
AND DOOR UNLOCK
DETECTION SW
REAR LH
BATTERY FAN RELAY
BATTERY ECUB C
B C
B CA B
A B
A B
BA11
B B
B BA C
B B
BJBK BI W± B
W± B
W± B
W± B
W± B
W± B
W± B
W± B W± BW±BW± B W±B W±B
W±B
W±B
W±B
W±B
JUNCTION
CONNECTORB J32 , J33A
JUNCTION
CONNECTORB J32 , J33
AB 1 W±B
W± B
HYBRID VEHICLE
CONTROL ECUCOMBINATION
SW COMBINATION SW
COMBINATION SW
TURN SIGNAL
FLASHER RELAYDOOR LOCK CONTROL
SW FRONT RH DOOR LOCK MOTOR,
DOOR KEY LOCK AND
UNLOCK SW AND DOOR
UNLOCK DETECTION
SW FRONT RH
B(
ECC)
(
GND1)
(
GND2)
A A
W± B A
W± B
B A B W±B W±B W±B W±B
W± BW± B
W± B 7
IQ1
2
IQ1
A AA
W± B A
B
A
B A
A A
A (
E)
(
E)
BLW±B
W±B
BC1 8A A
W±B
JUNCTION
CONNECTORB J18 , J19A W±B
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.