2001 TOYOTA PRIUS brake light

2001 PRIUS (EWD414U)
HEADLIGHT (w/ DAYTIME RUNNING LIGHT)
When the ignition SW is turned on ST position and ºREADYº signal from engine control module is sent to the daytime
running light relay via body ECU. If the parking brake pedal is depressed (Parking brake SW is on) at that time, the daytime
running light system does not operate. If the parking brake pedal is released (Parking brake SW is off), the daytime running
light system operates and the low beam headlight comes on.
HEAD RELAY
1±2 : Closed with the light control SW at HEAD position or the dimmer SW at FLASH position
Closed with the engine running and the parking brake lever is released (Parking brake SW off)
D3 DAYTIME RUNNING LIGHT RELAY
12±GROUND : Approx. 12 volts with the ignition SW at ON position
3±GROUND : Always approx. 12 volts
11±GROUND : Continuity with the parking brake lever pulled up
2±GROUND : Always continuity
8±GROUND : Continuity with the dimmer SW at HIGH or FLASH position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
B8A36H134J1737
B9B36H234J2037
C1036J137J27A37
C1336J1137J28B37
D336J12A37P237
D536J13B37
: RELAY BLOCKS
CodeSee PageRelay Blocks (Relay Block Location)
324Engine Room R/B No.3 (Engine Compartment Right)
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
1E
1F27Engine Room Main Wire and Engine Room J/B (Engine Compartment Left)
1J
gg(g)
2A
2B30Instrument Panel Wire and Instrument Panel J/B (Cowl Side Panel LH)
2C
()
2G31Engine Room Main Wire and Instrument Panel J/B (Cowl Side Panel LH)
2I31Cowl Wire and Instrument Panel J/B (Cowl Side Panel LH)2K31Cowl 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)
IA142Engine Room Main Wire and Cowl Wire (Cowl Side Panel LH)IA242Engine Room Main Wire and Cowl Wire (Cowl Side Panel LH)
ID142Instrument Panel Wire and Cowl Wire (Left Kick Panel)ID242Instrument Panel Wire and Cowl Wire (Left Kick Panel)
: GROUND POINTS
CodeSee PageGround Points Location
ID42Cowl Side Panel LHIE42Cowl Side Panel LH
IG42Cowl Side Panel RH
IH42Right Kick Panel
SYSTEM OUTLINE
SERVICE HINTS

2001 PRIUS (EWD414U)
S3 STOP LIGHT SW
2±1 : Closed with the brake pedal depressed
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
H1538J31B38R639
J1437J32A38R739
J30A38J33B38S337
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
2K31Cowl 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)
IB142Floor Wire and Cowl Wire (Cowl Side Panel LH)
: GROUND POINTS
CodeSee PageGround Points Location
BI46Left Side of Rear Pillar
BK46Back Panel Center
SERVICE HINTS

2001 PRIUS (EWD414U)
With the ignition SW turned on, the current flows to TERMINAL 15 of the body ECU through GAUGE fuse.
Voltage is applied at all times to TERMINAL (A) 11 of the body ECU through the TAIL relay. Coil side, and to TERMINAL (A)
2 through the HEAD relay coil side (w/o daytime running light) or through the daytime running light relay (w/ daytime running
light).
1. NORMAL LIGHTING OPERATION

With the light control SW turned to TAIL position, a signal is input into TERMINAL (A) 18 of the body ECU. Due to this signal,
the current flowing to TERMINAL (A) 11 of the body ECU flows to TERMINAL (A) 18 to TERMINAL 14 of the light control SW
to TERMINAL 16 to GROUND, and taillight relay causes taillights to turn on.

With the light control SW turned to HEAD position, a signal is input into TERMINALS (A) 17 and (A) 18 of the body ECU. Due
to this signal, the current flowing to TERMINAL (A) 2 of the body ECU flows to TERMINAL (A) 17 to TERMINAL 13 of the
light control SW to TERMINAL 16 to GROUND in the headlight circuit, and causes taillight and HEAD relay to turn the lights
on. The taillight circuit is same as above.
2. LIGHT AUTO TURN OFF OPERATION
With light on and ignition SW turned off (Input signal goes to TERMINAL 15 of the body ECU), when the driver's door is
opened (Input signal goes to TERMINAL 3 of the body ECU), the ECU operates and the current is cut off which flows from
TERMINAL (A) 11 of the body ECU to TERMINAL (A) 18 in taillight circuit and from TERMINAL (A) 2 to TERMINAL (A) 17 in
headlight circuit.
As a result, all lights are turned off automatically.
HEAD RELAY
2±1 : Closed with the light control SW at HEAD position or the dimmer SW at FLASH position
Closed with the engine running and the parking brake lever released (Parking brake SW off) [w/ daytime running light]
TAIL RELAY
3±5 : Closed with the light control SW at TAIL or HEAD position
D6 DOOR COURTESY SW LH
1±GROUND : Continuity with the front LH door open
B8 (A), B9 (B) BODY ECU
15±GROUND : Approx. 12 volts with the ignition SW at ON position
3±GROUND : Continuity with the front LH door open
(B) 9±GROUND : Always approx. 12 volts
(A) 1±GROUND : Always continuity
(A) 2±GROUND : Continuity with the light control SW at HEAD position
(A)11±GROUND : Continuity with the light control SW at TAIL or HEAD position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
B9B36F13D34J2037
C1336F1838J24A37
D336J1137J25B37
D638J12A37J2737
F11B34J13B37U137
F12C34J1737
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
1B27Engine Room Main Wire and Engine Room J/B (Engine Compartment Left)1F27Engine Room Main Wire and Engine Room J/B (Engine Compartment Left)
2C30Instrument Panel Wire and Instrument Panel J/B (Cowl Side Panel LH)2D30Instrument Panel Wire and Instrument Panel J/B (Cowl Side Panel LH)
2H31Engine Room Main Wire and Instrument Panel J/B (Cowl Side Panel LH)
2K31Cowl Wire and Instrument Panel J/B (Cowl Side Panel LH)
SYSTEM OUTLINE
SERVICE HINTS

2001 PRIUS (EWD414U)
When the ignition SW is turned to ACC position the current from the ACC fuse flows to TERMINAL 1 of the shift lock ECU, in
the ON position, the current from the ECU±IG fuse flows to TERMINAL 3 of the ECU.
1. SHIFT LOCK MECHANISM
With the ignition SW on, when a signal that the brake pedal is depressed (Stop light SW on) and a signal that the shift lever
is put in P position (Continuity between P1 and P of the shift lock control SW) is input to the ECU, the ECU operates and
current flows from TERMINAL 3 of the ECU to TERMINAL SLS+ of the shift lock solenoid to solenoid to TERMINAL SLS± to
TERMINAL 5 of the ECU to GROUND. This causes the shift lock solenoid to turn on (Plate stopper disengages) and the shift
lever can shift into position other than the P.
2. KEY INTERLOCK MECHANISM
With the ignition SW ON or ACC position, when the shift lever is put in P position (No continuity between P2 and P of shift
lock control SW), the current flowing from TERMINAL 4 of the ECU to the key interlock solenoid is cut off. This causes the
key interlock solenoid to turn off (Lock lever disengages from LOCK position) and the ignition key can be turned from ACC to
LOCK position.
S2 SHIFT LOCK ECU
1±GROUND : Approx. 12 volts with the ignition SW at ACC or ON position
3±GROUND : Approx. 12 volts with the ignition SW at ON position
5±GROUND : Always continuity
6±GROUND : Approx. 12 volts with the brake pedal depressed
S3 STOP LIGHT SW
2±1 : Closed with the brake pedal depressed
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
J1137J23B37J28B37
J14A37J24A37S237
J15B37J25B37S337
J2137J2637U137
J22A37J27A37
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
2D30Instrument Panel Wire and Instrument Panel J/B (Cowl Side Panel LH)
2I31Cowl Wire and Instrument Panel J/B (Cowl Side Panel LH)2K31Cowl 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)
ID142Instrument Panel Wire and Cowl Wire (Left Kick Panel)ID242Instrument Panel Wire and Cowl Wire (Left Kick Panel)
: GROUND POINTS
CodeSee PageGround Points Location
ID42Cowl Side Panel LH
SYSTEM OUTLINE
SERVICE HINTS

2001 PRIUS (EWD414U)
ABS
2A 7
2B 6 B 18 B2
A 10 9A10A
GAUGE FROM POWER SOURCE SYSTEM (
SEE PAGE 50)
2A 5
22 A
A 14
IH B 3B10 B4
ID1 3 ID1 1 ID1 2
B±W
V±R
V±R
B±W
L L L L
GR±B GR GR
GR±LL BRGR±G W P±B P±B
WP±B
W
GR±GW±LP±B
GR±G
GR± B CE B
13 7 1414
11 11B 2
B 3
44 13
EA EA
DATA LINK CONNECTOR 3 D 2 JUNCTION
CONNECTOR J16
COMBINATION METERB C10 , C11A BRAKE ECUB B10 , B11AC, B12 D, B13
TC D/G TSWA SP1
ENGINE CONTROL
MODULE E10 A/C AMPLIFIER A 7
GATEWAY ECU G 1
MP2+ MPD1 MPX+ MPD2 MPX± MPX1
MPX2
MPX+GR±L
TC SIL TS2K 2
B 5
R±Y
BRL
R±Y
4
PKB 15A
STOP
2K 9
R±B
1 2
B 1
STPSTOP
LIGHT SW S 3
G± W G± W
JUNCTION
CONNECTOR J26
JUNCTION
CONNECTOR J22
CEB
BODY ECUB 8
A ABS
BRAKE
A 16
A 15
IP1 1IP12 A E
A EJUNCTION
CONNECTORJ14 A

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

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

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