fuse TOYOTA PRIUS 2001 Service Repair Manual

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2001 PRIUS (EWD414U)
B HOW TO USE THIS MANUAL
Current is applied at all times through the STOP fuse to TERMINAL 2 of the stop light SW.
When the ignition SW is turned on, current flows from the GAUGE fuse to TERMINAL 8 of the light failure sensor, and also flows
through the rear lights warning light to TERMINAL 4 of the light failure sensor.
STOP LIGHT DISCONNECTION WARNING
When the ignition SW is turned on and the brake pedal is pressed (Stop light SW on), if the stop light circuit is open, the current
flowing from TERMINAL 7 of the light failure sensor to TERMINALS 1, 2 changes, so the light failure sensor detects the
disconnection and the warning circuit of the light failure sensor is activated.
As a result, the current flows from TERMINAL 4 of the light failure sensor to TERMINAL 11 to GROUND and turns the rear lights
warning light on. By pressing the brake pedal, the current flowing to TERMINAL 8 of the light failure sensor keeps the warning
circuit on and holds the warning light on until the ignition SW is turned off.
S6 STOP LIGHT SW
2±1 : Closed with the brake pedal depressed
L4 LIGHT FAILURE SENSOR
1, 2, 7±GROUND : Approx. 12 volts with the stop light SW on
4, 8±GROUND : Approx. 12 volts with the ignition SW at ON position
11±GROUND : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
C734L436R737
H1736R637S635
: RELAY BLOCKS
CodeSee PageRelay Blocks (Relay Block Location)
118R/B No.1 (Instrument Panel Left)

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: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
IB20Instrument Panel Wire and Instrument Panel J/B (Lower Finish Panel)
3C22Instrument Panel Wire and J/B No.3 (Instrument Panel Left Side)
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CodeSee PageJoining Wire Harness and Wire Harness (Connector Location)
IE142Floor Wire and Instrument Panel Wire (Left Kick Panel)
BV150Luggage Room Wire and Floor Wire (Luggage Compartment Left)
: GROUND POINTS
CodeSee PageGround Points Location
BL50Under the Left Quarter Pillar
BO50Back Panel Center
: SPLICE POINTS
CodeSee PageWire Harness with Splice PointsCodeSee PageWire Harness with Splice Points
I544Cowl WireB1850Luggage Room Wire
SYSTEM OUTLINE
SERVICE HINTS

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.

To Ignition SW
IG Terminal
Fuse
Voltmeter SW 1
Relay
SW 2Solenoid[A]
[B]
[C]
Ohmmeter
SW
Ohmmeter
Diode
Digital Type Analog Type
2001 PRIUS (EWD414U)
C TROUBLESHOOTING
VOLTAGE CHECK
(a)Establish conditions in which voltage is present at the check
point.
Example:
[A] ± Ignition SW on
[B] ± Ignition SW and SW 1 on
[C] ± Ignition SW, SW 1 and Relay on (SW 2 off)
(b)Using a voltmeter, connect the negative lead to a good ground
point or negative battery terminal, and the positive lead to the
connector or component terminal.
This check can be done with a test light instead of a voltmeter.
CONTINUITY AND RESISTANCE CHECK
(a)Disconnect the battery terminal or wire so there is no voltage
between the check points.
(b)Contact the two leads of an ohmmeter to each of the check
points.
If the circuit has diodes, reverse the two leads and check
again.
When contacting the negative lead to the diode positive side
and the positive lead to the negative side, there should be
continuity.
When contacting the two leads in reverse, there should be no
continuity.
(c)Use a volt/ohmmeter with high impedance (10 kW/V
minimum) for troubleshooting of the electrical circuit.

To Ignition SW
IG Terminal
Test Light
Relay Light
SW 2 SolenoidDisconnectShort [A]
Disconnect
DisconnectSW 1Fuse Case
Short [B]
Short [C]
Pull Up
Press Down Press DownPull Up
2001 PRIUS (EWD414U)
C
FINDING A SHORT CIRCUIT
(a)Remove the blown fuse and disconnect all loads of the fuse.
(b)Connect a test light in place of the fuse.
(c)Establish conditions in which the test light comes on.
Example:
[A] ± Ignition SW on
[B] ± Ignition SW and SW 1 on
[C] ± Ignition SW, SW 1 and Relay on (Connect the
Relay) and SW 2 off (or Disconnect SW 2)
(d)Disconnect and reconnect the connectors while watching the
test light.
The short lies between the connector where the test light
stays lit and the connector where the light goes out.
(e)Find the exact location of the short by lightly shaking the
problem wire along the body.
CAUTION:
(a) Do not open the cover or the case of the ECU unless
absolutely necessary. (If the IC terminals are touched,
the IC may be destroyed by static electricity.)
(b) When replacing the internal mechanism (ECU part) of
the digital meter, be careful that no part of your body or
clothing comes in contact with the terminals of leads
from the IC, etc. of the replacement part (spare part).
DISCONNECTION OF MALE AND FEMALE
CONNECTORS
To pull apart the connectors, pull on the connector itself, not
the wire harness.
HINT : C h e c k t o s e e w h a t k i n d o f connector you are
disconnecting before pulling apart.

2001 PRIUS (EWD414U)
E GLOSSARY OF TERMS AND SYMBOLS
BATTERY
Stores chemical energy and
converts it into electrical energy.
Provides DC current for the auto's
various electrical circuits.GROUND
The point at which wiring attaches to
the Body, thereby providing a return
path for an electrical circuit; without a
ground, current cannot flow.
CAPACITOR (Condenser)
A small holding unit for temporary
storage of electrical voltage.HEADLIGHTS
Current flow causes a headlight
filament to heat up and emit light. A
headlight may have either a single
(1) filament or a double (2) filament
1. SINGLE
FILAMENT
CIGARETTE LIGHTER
An electric resistance heating
element.2. DOUBLE
FILAMENT
CIRCUIT BREAKER
Basically a reusable fuse, a circuit
breaker will heat and open if too
much current flows through it.
Some units automatically reset when
cool, others must be manually reset.HORN
An electric device which sounds a
loud audible signal.
DIODE
A semiconductor which allows
current flow in only one direction.IGNITION COIL
Converts low±voltage DC current
into high±voltage ignition current for
firing the spark plugs.
DIODE, ZENERA diode which allows current flow in one
direction but blocks reverse flow only up
to a specific voltage. Above that potential,
it passes the excess voltage. This acts as
a simple voltage regulator.LIGHT
Current flow through a filament
causes the filament to heat up and
emit light.
PHOTODIODE
The photodiode is a semiconductor
which controls the current flow
according to the amount of light.LED (LIGHT EMITTING DIODE)
Upon current flow, these diodes emit
light without producing the heat of a
comparable light.
DISTRIBUTOR, IIA
Channels high±voltage current from
the ignition coil to the individual
spark plugs.METER, ANALOG
Current flow activates a magnetic
coil which causes a needle to move,
thereby providing a relative display
against a background calibration.
FUSEA thin metal strip which burns through
when too much current flows through it,
thereby stopping current flow and
protecting a circuit from damage.
FUSIBLE LINK
METER, DIGITAL
Current flow activates one or many
LED's, LCD's, or fluorescent
displays, which provide a relative or
digital display.
FUEL
FUSIBLE LINK
A heavy±gauge wire placed in high
amperage circuits which burns through on
overloads, thereby protecting the circuit.
The numbers indicate the crosssection
surface area of the wires.(for Medium Current Fuse)
(for High Current Fuse or
Fusible Link)MOTOR
A power unit which converts
electrical energy into mechanical
energy, especially rotary motion.
M

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)
KEY REMINDER AND LIGHT REMINDER BUZZER
The current always flows from GAUGE fuse to body ECU TERMINAL 15.
1. LIGHT REMINDER BUZZER SYSTEM
If you open the door of the driver's side when either headlight or taillight is on with ignition SW being off, the buzzer comes
on.
2. KEY REMINDER BUZZER SYSTEM
If you open the door of the driver's side when the ignition key is inserted in ignition SW being off, the buzzer comes on.
B8 (A), B9 (B) BODY ECU
(B) 9±GROUND : Always approx. 12 volts
(A) 1±GROUND : Always continuity
12±GROUND : Continuity with the ignition key in cylinder
D6 DOOR COURTESY SW FRONT LH
1±GROUND : Closed with the driver's door open
C10 (A) COMBINATION METER
(A)22±GROUND : Approx. 12 volts with the ignition SW at ON position
(A)21±GROUND : Always approx. 12 volts
(A)14±GROUND : Always continuity
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
A736E1036J13B37
B8A36F11B34J1737
B9B36F12C34J2037
C10A36F13D34J24A37
C11B36F1838J25B37
C1336G137J2737
D336J1137U137
D638J12A37
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
1B
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)2C30Instrument Panel Wire and Instrument Panel J/B (Cowl Side Panel LH)
2D
2G31Engine Room Main 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)
: CONNECTOR JOINING WIRE HARNESS AND WIRE HARNESS
CodeSee PageJoining Wire Harness and Wire Harness (Connector Location)
IA242Engine Room Main Wire and Cowl Wire (Cowl Side Panel LH)
IB142Floor Wire and Cowl Wire (Cowl Side Panel LH)
ID242Instrument Panel Wire and Cowl Wire (Left Kick Panel)
SYSTEM OUTLINE
SERVICE HINTS

2001 PRIUS (EWD414U)
When the ignition SW is turned ON, the current flows from WIPER fuse to wiper and washer SW TERMINAL 17 and front
wiper motor TERMINAL 2 or the current flows from WASHER fuse to washer motor TERMINAL 2.
1. LO POSITION
When the wiper and washer SW is at LO position, the current flows from wiper and washer SW TERMINAL 17 to TERMINAL
7 to front wiper motor TERMINAL 5 to TERMINAL 4 to GROUND, and the front wiper motor runs at low speed.
2. HI POSITION
When the wiper and washer SW is at HI position, the current flows from wiper and washer SW TERMINAL 17 to TERMINAL
8 to front wiper motor TERMINAL 3 to TERMINAL 4 to GROUND, and the front wiper motor runs at high speed.
3. INT POSITION
When the wiper and washer SW is at INT position, the wiper relay is activated and the current flows from wiper and washer
SW TERMINAL 17 to TERMINAL 2 to GROUND. This current activates the intermittent circuit, and the current flows from
wiper and washer SW TERMINAL 17 to TERMINAL 7 to front wiper motor TERMINAL 5 to TERMINAL 4 to GROUND, and
operates the front wipers.
4. WASHER CONTINUOUS OPERATION
When the wiper and washer SW is pulled to WASHER position (Washer SW ON position), the current from the WASHER
fuse flows to washer motor TERMINAL 2 to TERMINAL 1 to wiper and washer SW TERMINAL 11 to TERMINAL 2 to
GROUND, and operates the washer motor to emit a water spray. At the same time, the current flows from the WIP fuse to
wiper and washer SW TERMINAL 17 to TERMINAL 7 to front wiper motor TERMINAL 5 to TERMINAL 4 to GROUND, and
operates the front wiper motor.
C12 FRONT WIPER AND WASHER SW
2±GROUND : Always continuity
7±GROUND : Approx. 12 volts with the front wiper and washer SW at LO position
Approx. 2 to 12 seconds intermittently with the front wiper and washer SW at INT position
8±GROUND : Approx. 12 volts with the front wiper and washer SW at HI position
16±GROUND : Approx. 12 volts with the ignition SW on unless the front wiper motor at STOP position
17±GROUND : Approx. 12 volts the ignition SW at ON or ST position
F9 FRONT WIPER MOTOR
2±1 : Closed unless the wiper motor at STOP position
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
C1236J737W135
F934J1737
J137J1837
: JUNCTION BLOCK AND WIRE HARNESS CONNECTOR
CodeSee PageJunction Block and Wire Harness (Connector Location)
2G31Engine Room Main Wire and Instrument Panel J/B (Cowl Side Panel LH)
2I31Cowl Wire and Instrument Panel J/B (Cowl Side Panel LH)
2N31Floor 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)
IH142Floor Wire and Engine Room Main Wire (Left Kick Panel)
: GROUND POINTS
CodeSee PageGround Points Location
IE42Cowl Side Panel LH
IG42Cowl Side Panel RH
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)
DOOR LOCK CONTROL
The current is always sent from DOOR fuse to TERMINAL B of body ECU. When ignition SW is turned on, the current is sent
from GAUGE fuse to TERMINAL IG of the body ECU.
1. MANUAL LOCK OPERATION
When the door lock control SW (Power window master SW) is turned to LOCK position, the lock signal from TERMINAL
MPX1 of power window master SW is input to TERMINAL RX of body ECU to operate ECU. The current is sent from
TERMINAL ACT+ of ECU to each motor and the motor locks the doors by the current sent from TERMINAL ACT± of ECU to
GROUND.
2. MANUAL UNLOCK OPERATION
When the door lock control SW (Power window master SW) is turned to UNLOCK position, the unlock signal from
TERMINAL MPX1 of power window master SW is input to TERMINAL RX of body ECU to operate ECU. The current is sent
from TERMINAL ACT± of ECU to each motor and the motor unlocks the doors by the current sent from TERMINAL ACT+ of
ECU to GROUND.
3. DOOR KEY LOCK AND UNLOCK OPERATION
*Lock operation from the driver's side door
When the driver's side door is locked using the ignition key, all the doors are locked.
*Unlock operation from the driver's side door
When the driver's side door is unlocked once using the ignition key, only the driver's side door is unlocked. If this operation
is repeated within 3 seconds, all the other doors are unlocked.
*Lock operation from the front passenger's side door
When the front passenger's side door is locked using the ignition key, all the doors are locked.
*Unlock operation from the front passenger's side door
When the front passenger's side door is unlocked using the ignition key, all the doors are unlocked
B8 (A), B9 (B) BODY ECU
15±GROUND : Approx. 12 volts with the ignition SW at ON position
8±GROUND : Always approx. 12 volts
(B) 1±GROUND : Always continuity
D6, D7, D8, D9 DOOR COURTESY SW FRONT LH, RH, REAR LH, RH
1±GROUND : Closed with each of the door open
U1 UNLOCK WARNING SW
1±2 : Closed with the ignition key in the cylinder
: PARTS LOCATION
CodeSee PageCodeSee PageCodeSee Page
B8A36D1338J19B37
B9B36D1438J22A37
D436J1137J23B37
D638J12A37J24A37
D738J13B37J25B37
D838J14A37J2737
D938J15B37J3338
D1038J1637L438
D1138J1737P939
D1238J18A37U137
SYSTEM OUTLINE
SERVICE HINTS