engine TOYOTA PRIUS 2001 Service Repair Manual

H16901
Airbag Sensor Assembly Front Airbag Sensor (RH)
+SR
±SR A18
A189
20 B±W
BR±W IL13
4 B±W
BR±W 2
1 +SR
±SR IL1 DI±618
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
2001 PRIUS (RM778U)
DTC B1156/B1157/15 Front Airbag Sensor (RH) Malfunction
CIRCUIT DESCRIPTION
The front airbag sensor (RH) circuit consists of the airbag sensor assembly and front airbag sensor (RH).
For details of the function of each component, see OPERATION on page RS±2.
DTC B1156/B1157/15 is recorded when a malfunction is detected in the front airbag sensor (RH) circuit.
DTC No.DTC Detecting ConditionTrouble Area
B1156/B1157/15
Front airbag sensor (RH) malfunction

Front airbag sensor (RH)

Airbag sensor assembly

Wire harness

Engine room No. 2 wire harness
WIRING DIAGRAM
DI6PW±06

AB0119H03354
H03364H08348
Airbag
Sensor
Assembly Front Airbag
Sensor (RH)
(+)
+SR
(±)
±SR
ON
Engine Room No. 2
Wire Harness
u"
H03354H03362H08349
Airbag
Sensor
Assembly Front Airbag
Sensor (RH)
(+)+SR
(±)±SR Engine Room No. 2
Wire Harness
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±623
2001 PRIUS (RM778U)
8 Check engine room No. 2 wire harness (to B+).
PREPARATION:
Disconnect the engine room No. 2 wire harness connector on
the airbag sensor assembly side.
CHECK:
(a) Turn the ignition switch to ON.
(b) For the connector (on the RH front door wire harness
side) between the airbag sensor assembly and the en-
gine room No. 2 wire harness, measure the voltage be-
tween body ground and each of +SR and ±SR.
OK:
Voltage: Below 1 V
NG Repair or replace engine room No. 2 wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room No.
2 wire harness.
9 Check engine room No. 2 wire harness (to ground).
PREPARATION:
Disconnect the engine room No. 2 wire harness connector on
the airbag sensor assembly side.
CHECK:
For the connector (on the engine room No. 2 wire harness side)
between the airbag sensor assembly and the engine room No.
2 wire harness, measure the resistance between body ground
and each of +SR and ±SR.
OK:
Resistance: 1 MW or Higher
NG Repair or replace engine room No. 2 wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room No.
2 wire harness.

H03354H09507H08351
Airbag
Sensor
Assembly
Front Airbag
Sensor (RH)
(±) +SR
±SR
Engine Room No. 2
Wire Harness
(+)
u "
DI±624
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
2001 PRIUS (RM778U)
10 Check engine room No. 2 wire harness.
PREPARATION:
Disconnect the engine room No. 2 wire harness connector on
the airbag sensor assembly side.
CHECK:
For the connector (on the engine room No. 2 wire harness side)
between the airbag sensor assembly and the engine room No.
2 wire harness, measure the resistance between +SR and ±SR.
OK:
Resistance: 1 MW or Higher
NG Repair or replace engine room No. 2 wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room No.
2 wire harness.

H03352H09507H03360H08350
Airbag
Sensor
Assembly Front Airbag
Sensor (RH)
(+) +SR
(±)±SR
Engine Room No. 2
Wire Harness
+SR
±SR
u "
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±625
2001 PRIUS (RM778U)
11 Check engine room No. 2 wire harness.
PREPARATION:
(a) Disconnect the engine room No. 2 wire harness connec-
tor on the airbag sensor assembly side.
(b) Using a service wire, connect +SR and ±SR of the con-
nector (on the engine room No. 2 wire harness side) be-
tween the engine room No. 2 wire harness and the front
airbag sensor (RH).
CHECK:
For the connector (on the engine room No. 2 wire harness side)
between the airbag sensor assembly and the engine room No.
2 wire harness, measure the resistance between +SR and ±SR.
OK:
Resistance: Below 1 W
NG Repair or replace engine room No. 2 wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room No.
2 wire harness.

H16901
Airbag Sensor Assembly Front Airbag Sensor (LH)
+SL
±SL A1815
26 2
1 +SLIL1
±SL IL121
A18 W±R
BR
BR W±R DI±626
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
2001 PRIUS (RM778U)
DTC B1158/B1159/16 Front Airbag Sensor (LH) Malfunction
CIRCUIT DESCRIPTION
The front airbag sensor (LH) circuit consists of the airbag sensor assembly and front airbag sensor (LH).
For details of the function of each component, see OPERATION on page RS±2.
DTC B1158/B1159/16 is recorded when malfunction is detected in the front airbag sensor (LH) circuit.
DTC No.DTC Detecting ConditionTrouble Area
B1158/B1159/16
Front airbag sensor (LH) malfunction

Front airbag sensor (LH)

Airbag sensor assembly

Wire harness

Engine room main wire harness
WIRING DIAGRAM
DI6PX±06

H03354H16253H16297
Airbag
Sensor
Assembly Front Airbag
Sensor (LH)
(+)
+SL
(±)
±SL
ON
Engine Room Main
Wire Harness
u"
H03354H16252H16298
Airbag
Sensor
Assembly Front Airbag
Sensor (LH)
(+)+SL
(±)±SL Engine Room Main
Wire Harness
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±631
2001 PRIUS (RM778U)
8 Check engine room main wire harness (to B+).
PREPARATION:
Disconnect the engine room main wire harness connector on
the airbag sensor assembly side.
CHECK:
(a) Turn the ignition switch to ON.
(b) For the connector (on the LH front door wire harness side)
between the airbag sensor assembly and the engine
room main wire harness, measure the voltage between
body ground and each of +SL and ±SL.
OK:
Voltage: Below 1 V
NG Repair or replace engine room main wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room main
wire harness.
9 Check engine room main wire harness (to ground).
PREPARATION:
Disconnect the engine room main wire harness connector on
the airbag sensor assembly side.
CHECK:
For the connector (on the engine room main wire harness side)
between the airbag sensor assembly and the engine room main
wire harness, measure the resistance between body ground
and each of +SL and ±SL.
OK:
Resistance: 1 MW or Higher
NG Repair or replace engine room main wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room main
wire harness.

H03354H16251H16299
Airbag
Sensor
Assembly
Front Airbag
Sensor (LH)
(±) +SL
±SL
Engine Room Main
Wire Harness
(+)
u "
DI±632
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
2001 PRIUS (RM778U)
10 Check engine room main wire harness.
PREPARATION:
Disconnect the engine room main wire harness connector on
the airbag sensor assembly side.
CHECK:
For the connector (on the engine room main wire harness side)
between the airbag sensor assembly and the engine room main
wire harness, measure the resistance between +SL and ±SL.
OK:
Resistance: 1 MW or Higher
NG Repair or replace engine room main wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room main
wire harness.

H03352H16251H03360H16300
Airbag
Sensor
Assembly Front Airbag
Sensor (LH)
(+) +SL
(±)±SL
Engine Room Main
Wire Harness
+SL
±SL
u "
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
DI±633
2001 PRIUS (RM778U)
11 Check engine room main wire harness.
PREPARATION:
(a) Disconnect the engine room main wire harness connector
on the airbag sensor assembly side.
(b) Using a service wire, connect +SL and ±SL of the connec-
tor (on the engine room main wire harness side) between
the engine room main wire harness and the front airbag
sensor (LH).
CHECK:
For the connector (on the engine room main wire harness side)
between the airbag sensor assembly and the engine room main
wire harness, measure the resistance between +SL and ±SL.
OK:
Resistance: Below 1 W
NG Repair or replace engine room main wire har-
ness.
OK
Repair or replace harness or connector between airbag sensor assembly and engine room main
wire harness.

H15524
B±W
W5
2BB±O
GR
W±B ACC Relay 10A SRS ACC
5A AM1
FL Block No. 2 FL Block No. 1 15A AM2
Battery 100A
DC/DCB±G W±RA
J11
J/C W±G
W±R P±L1
2H
8
2C2
2E
4
2E
8
2K
2B 536
A18ACC
120A
1 1
F13 1
F12
1
F11 1B9 2
1J B1
2G2
2C ACC
2
67AM1
AM2 IG2MAIN
35
A18IG2 Airbag Sensor
Assembly Instrument Panel J/B
Ignition Switch
ID 12
3
Instrument Panel J/B Engine Room J/B DI±634
± DIAGNOSTICSSUPPLEMENTAL RESTRAINT SYSTEM
2001 PRIUS (RM778U)
DTC Normal Source Voltage Drop
CIRCUIT DESCRIPTION
The SRS is equipped with a voltage±increase circuit (DC±DC converter) in the airbag sensor assembly in
case the source voltage drops.
When the battery voltage drops, the voltage±increase circuit (DC±DC converter) functions to increase the
voltage of the SRS to normal voltage.
The diagnosis system malfunction display for this circuit is different from other circuits that is when the SRS
warning light remains lit up and the DTC is a normal code, source voltage drop is indicated.
Malfunction in this circuit is not recorded in the airbag sensor assembly, and the source voltage returns to
normal, the SRS warning light automatically goes off.
DTC No.Diagnosis
(Normal)Source voltage drop
WIRING DIAGRAM
DI6PY±07

I15477
Instrument Panel J/B
FL Block No. 2S3
Stop Light SW I15
Ignition SW
Engine Room J/BHybrid Vehicle
Control ECU
J25 ID1B±Y
ST1± IG2 AM2
1G±W
2
R±B2
H14
STP 1
H14 B±W
34
6 B±W
J24
B C B±W W±R
7
6
2
2C
15A AM21
2GW±R
9
1J 2
1B B
1
F12B±G
120A MAIN
Battery1
F13
1
F18J15
D J14
E G±W
Instrument Panel J/B
9
2K15A STOP
W
100A DC/DC
F11 1
2H
FL Block No. 1
1
F131
B±GS3
Stop Light SW J/C
J/C
FL Block No. 1
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±655
2001 PRIUS (RM778U)
WIRING DIAGRAM