1999 TOYOTA CAMRY ABS

± 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

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

F00067
IG1
GND ON
(+) (±) IG1
GND ON
(+) (±) IG1
GND ON
(+) (±)IG1
GND ON
(+) (±)
F00068
LOCK
GND (+)
(±) LOCK
GND (+)
(±) LOCK
GND (+)
(±)LOCK
GND (+)
(±)
DI±560
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
795 Author: Date:
3 Check voltage between terminals IG1 and GND of ABS actuator connector.
PREPARATION:
Disconnect ABS actuator connector.
CHECK:
(a) Turn the ignition switch ON.
(b) Measure voltage between terminals IG1 and GND of ABS
actuator harness side connector.
OK:
Voltage: 10 ± 14 V
OK Check and replace ABS ECU.
NG
4 Check continuity between terminals GND of ABS actuator connector and body
ground.
CHECK:
Measure resistance between terminal GND of ABS actuator
harness side connector and body ground.
OK:
Resistance: 1 W or less
NG Repair or replace harness or connector.
OK
Check for open circuit in harness and connector between ABS ECU and ECU±IG
(See page IN±31).

F00069
STP (+) (±)
DI±562
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
797 Author: Date:
2 Check voltage between terminal STP of ABS actuator and body ground.
PREPARATION:
Disconnect ABS actuator connector.
CHECK:
Measure voltage between terminal STP of ABS actuator har-
ness side connector and body ground when brake pedal is de-
pressed.
OK:
Voltage: 8 ± 14 V
OK Check and replace ABS ECU.
NG
3 Check for open circuit in harness and connector between ABS ECU and stop
light switch (See page IN±31).
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown on problem symptoms table (See page DI±545).

± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (BOSCH Made)
DI±563
798 Author: Date:
DTC 62 ABS ECU Malfunction
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
62ABS ECU continuously detects the proper operation of
ABS.
Battery

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.
INSPECTION PROCEDURE
1 Is DTC output?
Check DTC on page DI±539.
YES Repair circuit indicated by the code output.
NO
2 Is normal code displayed?
YES Check for short circuit in harness and connec-
tor between DLC1 or DLC2 and ABS ECU
(See page IN±31).
NO
3 Does ABS warning light go off?
YES Check for open and short circuit in harness and
connector of Tc circuit between ECU and DLC2
or DLC1.
NO
DI047±06