TOYOTA CAMRY 1999 Service Repair Manual

± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±519
754 Author: Date:
DTC 33, 34 Rear Speed Sensor Rotor Faulty
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
33, 34
The condition that the both rear side wheels' speed is
lower than the front wheels' speed at 20 km/h (12 mph) or
more for 20 sec. or more when the IG switch turns ON
and OFF , which is repeated in a sequence more than 8
times.

Rear axle hub

Right rear, left rear speed sensor

Rear speed sensor circuit
INSPECTION PROCEDURE
1 Check rear axle hub (See page SA±9).
NG Replace rear axle hub.
OK
2 Check rear speed sensor (See page DI±514).
NG Replace rear speed sensor.
OK
3 Check for open and short circuit in harness and connector between rear speed
sensor and ECU (See page IN±31).
NG Repair or replace harness and connector.
OK
Check and replace ABS ECU.
DI03L±03

F07156
Ignition
Switch
W24
AM1
IG1
B±YInstrument Panel J/B
19
1K
ECU±IG1JB±RJ/C
J12
C
CB±R13
A19ABS ECU
IG1
Instrument Panel J/B
21
1K
1B
AM1
B±R
FL Block
1
1
F4 F9
ALT
B±G
FL MAIN
Battery
IG A
Instrument
Panel Brace LH J11
Junction
ConnectorW±B
W±B12
A19
A1925GND1
GND2 DI±520
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
755 Author: Date:
DTC 41 IG Power Source Circuit
CIRCUIT DESCRIPTION
This is the power source for the ECU, hence the actuators.
DTC No.DTC Detecting ConditionTrouble Area
41
Condition 1. or 2. is detected:
1. Vehicle speed is at 3 km/h (1.9 mph) or more and ECU
terminal IG1 voltage is 9.5 V or less , which continues
for 10 sec. or more.
2. When IG1 terminal voltage is less than 9.5 V, there is
open circuit in the motor relay or in the solenoid relay, or
the solenoid circuit malfunction.

Battery

Charging system

Power source circuit
Fail safe function:
If trouble occurs in the power source circuit, the ECU cuts off current to the ABS solenoid relay and prohibits
ABS control.
WIRING DIAGRAM
DI03M±03

F00073
ECU±IGECU±IG
Instrument
Panel J/BECU±IG
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±521
756 Author: Date:
INSPECTION PROCEDURE
1 Check ECU±IG fuse.
PREPARATION:
Remove ECU±IG fuse from Instrument Panel J/B.
CHECK:
Check continuity of ECU±IG fuse.
OK:
Continuity
NG Check for short circuit in all the harness and
components connected to ECU±IG fuse (See at-
tached wiring diagram).
OK
2 Check battery positive voltage.
OK:
Voltage: 10 ± 14 V
NG Check and repair the charging system
5S±FE engine: (See page CH±1)
1MZ±FE engIne: (See page CH±1).
OK

F07151
ON
(+)(±)
IG1GND
GND
F07152F07216
LOCK
(±) GND
GND(+)
DI±522
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
757 Author: Date:
3 Check voltage between terminals IG1 and GND of ABS ECU connector.
PREPARATION:
Remove ABS ECU with connectors still connected.
CHECK:
(a) Turn the ignition switch ON.
(b) Measure voltage between terminals IG1 and GND of ABS
ECU connector.
OK:
Voltage: 10 ± 14 V
OK Check and replace ABS ECU.
NG
4 Check continuity between terminals GND of ABS ECU connector and body
ground.
PREPARATION:
Disconnect the connector from the ABS ECU.
CHECK:
Measure resistance between terminal GND of ABS ECU con-
nector 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 fuse (See page
IN±31).

F00124
Battery MAIN B±GF4 F91
ALT FL Block
B±R STOP Instrument Panel J/B
1C1B4
7Stop Light
Switch
2G±W
1R 1S5J27 J28J/C
Light Failure
Sensor
J/C
J40
BL
BP W±BG±W
A195
STPABS ECU
R
G±R
High
Mounted
Stop
LightRight
Stop
LightLeft
Stop
Light
A 1Instrument
Panel J/B
G±R W
11R
2 4
G±W
G±R
W±B
W±B
W±B AAC
W±B W±BH10 R11
R9
H10R9
R11 2
122
5 5 G±W
1
2 7
Under the
Left Center
PillarBack Panel
Center
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±523
758 Author: Date:
DTC 49 Stop Light Switch Circuit
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
49
ABS ECU terminal IG1 voltage is 9.5 V to 18.5 V and ABS
is in non±operation, the open circuit of the stop light switch
circuit continues for 0.3 sec. or more.
Stop light switch

Stop light switch circuit
WIRING DIAGRAM
INSPECTION PROCEDURE
1 Check operation of stop light.
CHECK:
Check that stop light lights up when brake pedal is depressed and turns off when brake pedal is released.
NG Repair stop light circuit (See page BE±37).
OK
DI03N±03

F07150
(+)(±) STP
DI±524
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
759 Author: Date:
2 Check voltage between terminal STP of ABS ECU and body ground.
PREPARATION:
Remove ABS ECU with connectors still connected.
CHECK:
Measure voltage between terminal STP of ABS ECU and body
ground when brake pedal is depressed.
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±501).

F07146
B±G
Fusible
Link
Block
F5 1
F4
1
FL
Main B±G
Battery3
3ABSABS Motor
Relay
2 13
43
3
Engine Room R/B No.3GR±R GR±R1
IK126
A19 R+ABS ECU
GR±L1
A18 MR
W±R2
A4
A41
W±B
EAABS Actuator
3
A4R±W10
A18 MT ALT
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±525
760 Author: Date:
DTC 51 ABS Pump Motor Lock
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
51ABS actuator pump motor is not operating normally.
ABS pump motor
Fail safe function:
If trouble occurs in the ABS pump motor, the ECU cuts off current to the ABS solenoid relay and prohibits
ABS control.
WIRING DIAGRAM
DI4KW±01

F03291
(±)
(+)12 A4
DI±526
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
761 Author: Date:
INSPECTION PROCEDURE
1 Check operation of ABS & TRAC pump motor.
PREPARATION:
Disconnect the ABS actuator connector.
CHECK:
Connect positive
lead to terminal A4±2 and negative  lead
to terminal A4 ± 1 of the ABS actuator connector, check that the
pump motor is operates.
OK:
The running sound of the pump motor should be
heard.
OK Check for open circuit in harness and connec-
tor between ABS motor relay, ABS actuator and
ABS ECU (See page IN±31).
NG
Replace ABS actuator.

± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
DI±527
762 Author: Date:
DTC Always ON ABS ECU Malfunction
CIRCUIT DESCRIPTION
DTC No.DTC Detecting ConditionTrouble Area
Always ONABS ECU internal malfunction is detected.
ECU

Battery
Fail safe function:
If trouble occurs in the power source circuit, the ECU cuts off current to the ABS solenoid relay and prohibits
ABS control.
INSPECTION PROCEDURE
1 Is DTC output?
Check DTC on page DI±493.
YES Repair circuit indicated by the code output.
NO
2 Is normal code displayed?
YES Check ABS solenoid relay. Check for short cir-
cuit in harness and connector between ABS so-
lenoid relay and DLC1 (See page IN±31).
NO
3 Is ABS warning light go off?
YES Check for open or short circuit in harness and
connector between ECU±IG fuse and ABS ECU
(See page IN±31).
NO
DI03P±04

DI±528
± DIAGNOSTICSANTI±LOCK BRAKE SYSTEM (DENSO Made)
763 Author: Date:
4 Check battery positive voltage.
CHECK:
Check the battery positive voltage.
OK:
10 ± 14 V
NG Check and repair the charging system
5S±FE engine: (See page CH±1)
1MZ±FE engine: (See page CH±1).
OK
5 Check ABS warning light.
PREPARATION:
(a) Disconnect the connector from the ABS ECU.
(b) Turn the ignition switch ON.
CHECK:
Check the ABS warning light goes off.
OK Check and replace ABS ECU.
NG
Check for short circuit in harness and connector between ABS warning light, DLC1, DLC2, and
ABS ECU (See page IN±31).