2001 TOYOTA PRIUS Service Repair Manual

F12680
Battery B±G F13 1
FL Block
No. 2 F11
1
H15
High Mounted
Stop Light 2HR±B STOP
C Instrument Panel J/B
W
2 1Stop Light Switch
G±W
5IB1 2K
2G±W
A
AJ14
J/C
G±W 9Brake ECU
STP
G±WB11
2 1
W±B9 1 2E
BI 1
BKR7
Stop Light RH
W±B W±BW±BJ30
5E
R6
Stop Light LH
G±W
J30
J31J31C
G±W
G±W W±B
C C
C
J32 J33J33J/C J/C1
FL Block
No. 1E
DC/DC
MAIN DI±408
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
2001 PRIUS (RM778U)
DTC C1249/49 Stop Light Switch Circuit
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
C1249/49
When the ignition switch is ON, the condition that the termi-
nal STP in brake ECU is 3 ± 12 V continues for 1 sec. or
more.
Stop light switch

Stop light switch circuit
WIRING DIAGRAM
DI1GO±09

F12407
LOCK
STP
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
DI±409
2001 PRIUS (RM778U)
INSPECTION PROCEDURE
1 Check operation of the stop light switch.
CHECK:
Check that the stop light lights up when brake pedal is depressed and turns off when the brake pedal is re-
leased.
OK Go to step 3.
NG
2 Check stop light circuit (See page BE±2).
NG Repair or replace stop light circuit.
OK
3 Check voltage between terminal STP of brake ECU and body ground.
PREPARATION:
Remove the brake ECU with connectors still connected.
CHECK:
Measure voltage between terminal STP of brake ECU and body
ground when brake pedal is depressed.
OK:
Voltage: 8 ± 14 V
OK Check and replace brake ECU.
NG

DI±410
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
2001 PRIUS (RM778U)
4 Check for open circuit in harness and connector between brake ECU and stop
light switch (See page IN±41).
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection on prob-
lem symptoms table (See page DI±365).

F12681
Brake ECU
B2
2 6
AA 1
1 ABS
No. 2
Engine Room J/B22
2 2
22
14
22
Y 1
3 FL
Block No. 12
2
J1
J/CL±O
5IA2
LG±R
13R1+
R2+ Y±B
W±L F12
IE2 G±W W±L
Battery 1B
6
H6 H6
B±G 1K
Hydraulic Brake
Booster7
W±BY±G14
3Y±G
MR2MR1
MTT
MT+
MT± 29
27
28
18 ABS
No. 3
FL
Block No. 2B
1K
F13H5
H6
H5
H5
H5
W±B W±B
AAY±B
B11
B13
B10
B13
B10
B10
B10
J7
J/CEngine
Room
R/B No. 2 Hydro
Motor
Relay
No. 2 Hydro
Motor
Relay
No. 1 1
23
43
4 2 1
G
MAIN
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM WITH EBD & RBS
DI±411
2001 PRIUS (RM778U)
DTC C1251/51 Hydraulic Brake Booster Pump Motor
Malfunction
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
C1251/51
Either of the following 1. or 2. is detected:
1. After turning the ignition switch ON, the current of more
than 28A flows to the motor for more than 1 sec.
2. After turning the ignition switch ON, less than 7A
change in current is detected more than 3 times in a row
when the motor is ON.
Hydraulic brake booster pump motor
WIRING DIAGRAM
DI298±06