TOYOTA CAMRY 1999 Service Repair Manual

DI08L±13
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±879
111 4 Author: Date:
PROBLEM SYMPTOMS TABLE
SymptomSuspect AreaSuspect AreaSee pageSee
page
SET not occourring or CANCEL occurring.
(DTC is Normal)
3. Main Switch Circuit
(Cruise control switch)
4. Vehicle Speed Sensor
5. Control Switch Circuit
(Cruise control switch)
6. Stop Light Switch Circuit
7. Park/Neutral Position Switch Circuit
8. Clutch Switch
9. Actuator Motor Circuit
10.Cruise Control Cable
11. Cruise Control ECU
DI±912
DI±888
DI±892
DI±898
DI±904
DI±907
DI±881
DI±918
IN±31
SET not occurring or CANCEL occurring.
(DTC dose not output)1. ECU Power Source Circuit
2. Cruise Control ECUDI±909
IN±31
Actual vehicle speed deviates above or below the set speed.
1. Cruise Control Cable
2. Vehicle Speed Signal Abnormal
3. Electronically Controlled Transmission
Communication Circuit
4. Actuator Motor Circuit
5. Idle Signal Circuit
(Main throttle position sensor)
6. Cruise Control ECUDI±918
DI±891
DI±901
DI±881
DI±895
IN±31
Gear shifting frequent between 3rd O/D when driving on uphill
road. (Hurting)1. Electronically Controlled Transmission
Communication Circuit
2. Cruise Control ECU
DI±901
IN±31
Cruise control not cancelled, even when brake pedal is de-
pressed.
1. Cruise Control Cable
2. Stop Light Switch Circuit
3. Actuator Motor Circuit
4. Cruise Control ECUDI±918
DI±898
DI±881
IN±31
Cruise control not cancelled, even when transmission is shifted to
ºNº postion.
1. Cruise Control Cable
2. Park/Neutral Position Switch Circuit
3. Actuator Motor Circuit
4. Cruise Control ECUDI±918
DI±904
DI±881
IN±31
Cruise control not cancelled, even when clutch pedal is de-
pressed.
1. Cruise Control Cable
2. Clutch Switch Circuit
3. Actuator Motor Circuit
4. Cruise Control ECUDI±918
DI±907
DI±881
IN±31
Control switch does not operate.
(SET/COAST, ACC/RES, CANCEL not possible)
1. Cruise Control Cable
2. Control Switch Circuit
3. Actuator Motor Circuit
4. Cruise Control ECUDI±918
DI±892
DI±881
IN±31
SET possible at 40 km/h (25 mph) or less, or CANCEL does not
operate at 40 km/h (25 mph) or less.
1. Cruise Control Cable
2. Vehicle Speed Signal Abnormal
3. Actuator Motor Circuit
4. Cruise Control ECUDI±918
DI±891
DI±881
IN±31
Poor response is in ACCEL and RESUME modes.
1. Cruise Control Cable
2. Electronically Controlled Transmission
Communication Circuit
3. Actuator Motor Circuit
4. Cruise Control ECUDI±918
DI±901
DI±881
IN±31
O/D does not resume, even though the road is not uphill.
1. Electronically Controlled Transmission
Communication Circuit
2. Cruise Control ECU
DI±901
IN±31

DI±880
± DIAGNOSTICSCRUISE CONTROL SYSTEM
111 5 Author: Date:
DTC memory is erased.1. Cruise Control ECUIN±31
DTC is not output, or is output when should not be.1. Diagnosis Circuit
2. Cruise Control ECUDI±916
IN±31
Cruise MAIN indicator light remains ON or falls to light up.1. Cruise MAIN Indicator Light Switch CircuitDI±914

DI08M±12
Duty Ratio =A + BA
x 100 (%)
ON
OFFA
B
1 cycle
I00280
Cruise Control ECU
MC 7
MO R±B Cruise Control Actuator

Actuator Motor
R±G 1 2
15
C15 C15
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±881
111 6 Author: Date:
CIRCUIT INSPECTION
DTC 11, 15 Actuator Motor Circuit
CIRCUIT DESCRIPTION
The actuator motor is operated by signals from the ECU. Acceleration and deceleration signals are trans-
mitted according to changes in the Duty Ratio (See below).
Duty Ratio
The duty ratio is the ratio of the period of continuity in one cycle. For example, if A is the period of continuity
in one cycle, and B is the period of non±continuity.
DTC No.Detection ItemTrouble Area
11Short in actuator motor circuit.
Actuator motor
Harness or connector between cruise control ECU and
actuator motor
Cruise control ECU
15Open in actuator motor circuit.Actuator motor
WIRING DIAGRAM

I00004
I00151
ON
2
1
DI±882
± DIAGNOSTICSCRUISE CONTROL SYSTEM
111 7 Author: Date:
INSPECTION PROCEDURE
1 Check resistance between terminals MO and MC of actuator motor.
PREPARATION:
(a) Turn ignition switch ON.
(b) Disconnect the actuator connector.
CHECK:
Measure resistance between terminals 1 and 2.
HINT:
If control plate is in fully opened or fully closed positions, resis-
tance can not be measured.
OK:
Resistance: more than 4.2 W
NG Replace cruise control actuator.
OK
2 Check for open and short in harness and connectors between cruise control
ECU and actuator motor (See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace cruise control ECU.
(See page IN±31).

I00281
Cruise Control ECU
C15
G±B
2 1 34W±B
3
STOP Fuse8 Stop Light Switch
4
R±Y
Stop Lights Cruise Control Actuator

Actuator Magnetic Clutch
J7
J7AAJ/C
W±B
1J
1J
W±B
A
J/C
IG 8
7
J11Instrument
Panel J/BL
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±883
111 8 Author: Date:
DTC 12 Actuator Magnetic Clutch Circuit
CIRCUIT DESCRIPTION
This circuit turns on the magnetic clutch inside the actuator during cruise control operation according to the
signal from the ECU. If a malfunction occurs in the actuator or speed sensor, etc. during cruise control opera-
tion, the rotor shaft between the motor and control plate is released.
When the brake pedal is depressed, the stop light switch turns on, supplying electrical power to the stop light.
Power supply to the magnetic clutch is mechanically cut and the magnetic clutch is turned OFF.
When driving downhill, if the vehicle speed exceeds the set speed by 15 km/h (9 mph), the ECU turns the
safety magnet clutch OFF. If the vehicle speed later drops to within 10 km/h (6 mph), cruise control at the
set speed is resumed.
DTC No.Detection ItemTrouble Area
12Short in actuator magnetic clutch circuit.
Open (0.8 sec.) in actuator magnetic clutch circuit.
STOP Fuse
Stop light switch
Actuator magnetic clutch
Harness or connector between cruise control ECU and
actuator magnetic clutch, actuator magnetic clutch and body
ground
Cruise control ECU
WIRING DIAGRAM
DI08N±12

I00157
Instrument panel junction block No.1:
STOP Fuse
I00133
21
43
DI±884
± DIAGNOSTICSCRUISE CONTROL SYSTEM
111 9 Author: Date:
INSPECTION PROCEDURE
1 Check STOP fuse.
PREPARATION:
(a) Turn ignition switch OFF.
(b) Remove the STOP fuse from instrument panel junction
block No.1.
CHECK:
Check fuse continuity.
OK:
There is continuity.
NG Replace STOP fuse.
OK
2 Check stop light switch.
PREPARATION:
Disconnect the stop light switch connector.
CHECK:
Check continuity between terminals.
Switch positionContinuity
Switch pin free
(Brake pedal depressed)1 ± 2
Switch pin pushed in
(Brake pedal released)3 ± 4
NG Replace stop light switch.
OK

I00311
4
3
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±885
1120 Author: Date:
3 Check resistance between terminals L and GND of actuator magnetic clutch.
PREPARATION:
(a) Turn ignition switch OFF.
(b) Disconnect the actuator connector.
CHECK:
Measure resistance between terminals 3 and 4.
OK:
Resistance: 34.65 ± 42.35 W.
NG Replace cruise control actuator.
OK
4 Check for open and short in harness and connectors between cruise control
ECU and actuator magnetic clutch, actuator magnetic clutch and body ground
(See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace cruise control ECU
(See page IN±31).

I00055
4
3(+)
(±)
DI±886
± DIAGNOSTICSCRUISE CONTROL SYSTEM
1121 Author: Date:
DTC 14 Actuator Mechanical Malfunction
CIRCUIT DESCRIPTION
The circuit detects the rotation position of the actuator control plate and sends a signal to the ECU.
DTC No.Detection ItemTrouble Area
14Cruise control actuator mechanical malfunction.

Actuator lock: (motor, arm)

Actuator motor

Cruise control ECU
WIRING DIAGRAM
See page DI±881.
INSPECTION PROCEDURE
1 Check cruise control actuator arm locking operation
PREPARATION:
(a) Turn ignition switch OFF.
(b) Disconnect the actuator connector.
CHECK:
Connect the positive (+) lead from the battery to the terminal 3
of actuator and the negative (±) lead to terminal 4.
NOTICE:
Do not connect the high tension cables to the wrong bat-
tery terminal. The cruise control actuator will be damaged.
Move the control plate by hand.
OK:
Control plate doesn't move.
NG Replace cruise control actuator.
OK
DI08O±12

I08437
Fully open side
Fully Closed sideControl plate
Control plate4
321
4
321
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±887
1122 Author: Date:
2 Check cruise control actuator operation.
PREPARATION:
(a) Turn ignition switch OFF.
(b) Disconnect the actuator connector.
CHECK:
Connect the positive (+) lead from the battery to terminals 1 and
3 of actuator, connect the negative (±) lead to terminals 2 and
4 of actuator.
OK:
Control arm moves to fully open side
CHECK:
Connect the positive (+) lead from the battery to terminals 2 and
3 of actuator, connect the negative (±) lead to terminals 1 and
4 of actuator.
OK:
Control arm moves to fully colsed side
NG Replace cruise control actuator.
OK
3 Check harness and connector between cruise control ECU and cruise control ac-
tuator (See page IN±31).
NG Repair or replace harness or connector.
OK
Check and replace cruise control ECU
(See page IN±31).

I00292
Vehicle Speed Sensor
ECUCombination Meter
Cruise Control ECU
4 pulses/
1 rotation
of rotor shaft4 pulses/
1 rotation
of rotor shaft
I00282
Cruise Control ECU
12
SPDV±W V±WB
BJ15
J/CIG3
3
V±W14
Combination Meter
15
6
Speedo
±meter
P L
IJ12IJ17
P
3L
2
SI
SE
IG+
1
R±Lto GAUGE Fuse
C15
C9 C9
C10
Speed
Sensor DI±888
± DIAGNOSTICSCRUISE CONTROL SYSTEM
1123 Author: Date:
DTC 21 Open in Vehicle Speed Sensor Circuit
CIRCUIT DESCRIPTION
The signal from the vehicle speed sensor circuit is sent to cruise control ECU as vehicle speed signal.
The rotor shaft is driven by the gear of the transmission.
For each rotation of the shaft, the vehicle speed sensor sends a 4±pulse signal through the combination
meter to the cruise control ECU (See the following installation).
This signal is converted inside the combination meter and sent as a 4±pulse signal to the cruise control ECU.
The ECU calculates the vehicle speed from this pulse frequency.
DTC No.Detection ItemTrouble Area
21Speed signal is not input to the cruise control ECU while cruise
control is set.

Combination meter

Harness or connector between cruise control ECU and com-
bination meter, combination meter and vehicle speed sensor

Vehicle speed sensor

Cruise control ECU
WIRING DIAGRAM
DI08P±12