TOYOTA CAMRY 1999 Service Repair Manual

F00064
LOCK
1918 17
16
(+)(±) LOCK
1918 17
16
(+)(±)
A6 LOCK
1918 17
16
(+)(±)
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
DI±549
784 Author: Date:
INSPECTION PROCEDURE
1 Check voltage between terminals A6 ± 17, 18 and A6 ± 16, 19 of ABS actuator
connector.
PREPARATION:
Disconnect the ABS actuator connector.
CHECK:
Measure the voltage between terminals A6 ± 17, 18 and A6 ±
16, 19 of ABS actuator harness side connector.
OK:
Voltage: 10 ± 14 V
NG Check and replace fuses.
Check and repair harness or connector.
OK
If the same code is still output after the DTC is deleted, check the contact condition of each con-
nection.
If the connections are normal, the ECU may be defective.

F03949
Actuator Assembly
BatteryActuator Assembly
MAINB±GF4 1 ALT
FL
Block 1F5 B±G3
ABS
12 3
Engine
Room R/B
No.3L
L
18
A6
+B+BA6
Valve Relay
Motor Relay17
A6 16 GND2
W±BEA
W±B
W±B 19
A6GND1 ECU DI±550
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
785 Author: Date:
DTC 21, 22, 23, 24 ABS Solenoid Valve Circuit
CIRCUIT DESCRIPTION
This solenoid goes on when signals are received from the ECU and controls the pressure acting on the wheel
cylinders thus controlling the braking force.
DTC No.DTC Detecting ConditionTrouble Area
21, 22, 23, 24Solenoid valve signal does not match to the check result.
Each solenoid valve
Fail safe function:
If trouble occurs in the actuator solenoid valve circuit, the ECU cuts off current to the ABS solenoid valve
relay and prohibits ABS control.
WIRING DIAGRAM
DI042±08

± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
DI±551
786 Author: Date:
INSPECTION PROCEDURE
1 Check the DTC once more.
PREPARATION:
(a) Clear the DTC (See page DI±539).
(b) Turn the ignition switch OFF.
CHECK:
Turn the ignition switch ON, and check if the same DTC is stored in the memory.
NO No problem.
YES
Replace ABS ECU.

BR3583
BR3582F00010
RotorSpeed Sensor
Magnet
To ECU
+V
±VHigh Speed
Low Speed
CoilNS
DI±552
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
787 Author: Date:
DTC31, 32, 33, 34, 35, 36, 38, 39Speed Sensor Circuit
CIRCUIT DESCRIPTION
The speed sensor detects wheel speed and sends the ap-
propriate signals to the ECU. These signals are used to control
the ABS system. The front and rear rotors each have 48 serra-
tions.
When the rotors rotate, the magnetic field emitted by the perma-
nent magnet in the speed sensor generates an AC voltage.
Since the frequency of this AC voltage changes in direct propor-
tion to the speed of the rotor, the frequency is used by the ECU
to detect the speed of each wheel.

DTC No.DTC Detecting ConditionTrouble Area
31, 32, 33, 34
Detection of any of conditions from 1. through 3.:
1. Vehicle speed is more than 40 km/h (25 mph), pulses
are not input for 0.01 sec.
2. After the initial start or restart and when the vehicle
speed has reached 12 km/h (7 mph), the wheel with 0
km/h (0 mph) of wheel speed is detected.
3. After the initial start or restart and when the vehicle
speed has reached 70 km/h (44 mph), front wheel with 0
km/h (0 mph) of wheel speed is detected.

Right front, left front, right rear, left rear speed sensor

Each speed sensor circuit

Sensor installation

ECU
35, 36, 38, 39Detecting abnormality in the resistance value of each speed
sensor.
Right front, left front, right rear, left rear speed sensor

Each speed sensor circuit

ECU
HINT:

DTC No. 31 and 35 are for the right front speed sensor.

DTC No. 32 and 36 are for the left front speed sensor.

DTC No. 33 and 38 are for the right rear speed sensor.

DTC No. 34 and 39 are for the left rear speed sensor.
Fail safe function:
If trouble occurs in the speed sensor circuit, the ECU cuts off current to the ABS solenoid valve relay and
prohibits ABS control.
DI043±04

F00086
Right Front
Speed Sensor
Left Front
Speed Sensor
Right Rear
Speed Sensor
Left Rear
Speed SensorECU
FR+
FR±
FL+
FL±
RR+
RR±
RL+
RL± A6
A6
A6
A6
A6
A6
A6
A65
4
7
6
3
1
9
8 W
B
R
G
P
L
Y
BRR
G
PP
L
L
Y
Y
BR
BR 2
1
2
1
1
2
1
2IK2
IL1IK3
ID1IK2
IL1 IK3
ID1IK3
IK3 22 1
6
1
3
93
9 6Right Front
Speed Sensor
Left Front
Speed Sensor
Right Rear
Speed Sensor
Left Rear
Speed SensorECU
FR+
FR±
FL+
FL±
RR+
RR±
RL+
RL± A6
A6
A6
A6
A6
A6
A6
A65
4
7
6
3
1
9
8 W
B
R
G
P
L
Y
BRR
G
PP
L
L
Y
Y
BR
BR 2
1
2
1
1
2
1
2IK2
IL1IK3
ID1IK2
IL1 IK3
ID1IK3
IK3 22 1
6
1
3
93
9 6
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
DI±553
788 Author: Date:
WIRING DIAGRAM

R14205
1
2
R14213
12 12
12
12
12
1212
DI±554
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
789 Author: Date:
INSPECTION PROCEDURE
1 Check speed sensor.
Front:
PREPARATION:
(a) Remove the front fender liner.
(b) Disconnect the speed sensor connector.
CHECK:
Measure resistance between terminals 1 and 2 of speed sensor
connector.
OK:
Resistance: 0.6 ± 2.5 kW
CHECK:
Measure resistance between terminals 1 and 2 of speed sensor
connector and body ground.
OK:
Resistance: 1 MW or higher
Rear:
PREPARATION:
(a) Remove the seat cushion and side seatback.
(b) Disconnect the speed sensor connector.
CHECK:
Measure resistance between terminals 1 and 2 of speed sensor
connector.
OK:
Resistance: 1.2 ± 2.3 kW
CHECK:
Measure resistance between terminals 1 and 2 of speed sensor
connector and body ground.
OK:
Resistance: 1 MW or higher
NG Replace speed sensor.
NOTICE:
Check the speed sensor signal last (See page DI±539).
OK

BR3795
OK NG OK NG
OK NGOK NG
R00948
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
DI±555
790 Author: Date:
2 Check for open and short circuit in harness and connector between each speed
sensor and ECU (See page IN±31).
NG Repair or replace harness or connector.
OK
3 Check speed sensor installation.
CHECK:
Check the speed sensor installation.
OK:
The installation bolt is tightened properly and there is
no clearance between the sensor and steering
knuckle or rear axle carrier.
NG Replace speed sensor.
NOTICE:
Check the speed sensor signal last (See page DI±539).
OK
4 Check sensor rotor and sensor tip.
Front:
PREPARATION:
Remove the front drive shaft (See page SA±17 or SA±26).
CHECK:
Check the sensor rotor serrations.
OK:
No scratches or missing teeth or foreign objects.
PREPARATION:
Remove the front speed sensor (See page BR±68).
CHECK:
Check the sensor tip.
OK:
No scratches or foreign objects on the sensor tip.

R00947
DI±556
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
791 Author: Date:
Rear:
PREPARATION:
Remove the axle hub (See page SA±52).
CHECK:
Check the sensor rotor serrations.
OK:
No scratches or missing teeth or foreign objects.
PREPARATION:
Remove the rear speed sensor (See page BR±70).
CHECK:
Check the sensor tip.
OK:
No scratches or foreign objects on the sensor tip.
NG Replace sensor rotor or speed sensor.
NOTICE:
Check the speed sensor signal last (See page DI±539).
OK
Check and replace ABS ECU.

± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
DI±557
792 Author: Date:
DTC 37 Speed Sensor Rotor Faulty
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
37
Detection of any of conditions from 1. through 3.:
1. Occurrence of differential to some degree in the wheel
speed between the front and rear wheels of either left or
right side of the vehicle and the front left and right
wheels. (Detection of differential in mini tire size, spin-
ning wheel and decelerating wheel.)
2. Continuous ABS control for 60 sec. or more.
3. Interference on 1 or more wheels for 20 sec. with the
brake pedal depressed, or for 5 sec. when the brake
pedal is not depressed.

Speed sensor

Sensor rotor

ECU
INSPECTION PROCEDURE
1 Check sensor rotor (See page DI±552).
NG Replace sensor rotor.
OK
2 Check speed sensor (See page DI±552).
NG Replace speed sensor.
OK
3 Check for open and short circuit in harness and connector between speed sen-
sor and ECU (See page IN±31).
NG Repair or replace harness and connector.
OK
Check and replace ABS ECU.
DI044±04

F03950
Actuator Assembly LB±R
IG1Actuator Assembly LB±R
IG1Actuator Assembly LB±R
IG1Actuator Assembly LB±R
IG1Actuator Assembly L
IG1
BatteryMAINB±G1
F4 ALTFL
Block 1F5 B±G3
ABS
12
Engine
Room R/B
No.3 3L
18
A617
A6
+B+B
Valve Relay
Motor Relay
GND2
A6
1615
A65
B±R
IK3B±R
C
C
J12 J/C
ECU
GND119
A6W±B
W±B
W±B
EAECU±IG
Instrument
Panel J/B 1J
9 DI±558
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
793 Author: Date:
DTC 41 Power Source Circuit
CIRCUIT DESCRIPTION
This is the power source for the ECU, hence the actuators.
DTC No.DTC Detecting ConditionTrouble Area
41
Vehicle speed at about 6 km/h (4 mph), low battery voltage
is less than 9.4 V at the time of non±operation of ABS
control or less than 8.8 V at the time of operation of ABS
control, and high battery voltage is more than 17.4 V.
Battery

Charging system

Power source circuit

ECU
Fail safe function:
If trouble occurs in the power source circuit, the ECU cuts off current to the ABS solenoid valve relay and
prohibits ABS control.
WIRING DIAGRAM
DI045±08