1986 TOYOTA CAMRY V20 air condition

Anti±lock Brake System Circuit
INSPECTION OF SYSTEM CIRCUIT
1. INSPECT SYSTEM CIRCUIT WITH CONNECTOR
CONNECTED
(a) Remove the A.B.S. computer.
(b) Using a voltmeter with high impedance (10 K

/V
minimum), measure the voltage at each terminal and
body ground.
If the circuit is not as specified, check and repair or re-
place the trouble part shown in the table above.
Ignition switch on and ºANTI LOCKº warning light goes on
Ignition switch on and ºANTI LOCKº warning light goes on
Ignition switch on and ºANTI LOCKº warning light goes onIgnition switch on and ºANTI LOCKº warning light goes on Ignition switch on and ºANTI LOCKº warning light goes on
Ignition switch on and ºANTI LOCKº warning light goes on
Check connector connectedºANTI LOCKº
warning light bulb
Check connector disconnected
Check connector,
computer Actuator, control
relays
AST ± Body groundSRR ± Body groundSRl ± Body ground SFR ± Body groundSFL ± Body ground
W ± Body ground
T ± Body ground Tester Connection
Ignition switch on Ignition switch on
Ignition switch on Ignition switch on
Ignition switch on Ignition switch on
Battery voltage Battery voltage
Battery voltage Battery voitage Battery voltage
Battery voltage Battery voltageTrouble Part
About 0 V
About 0 V About 0 V About 0 V
About 0 V
About 0 V
About 0 V ConditionVoltage
± BRAKE SYSTEMAnti±lock Brake System (A.B.S.)BR±102

2. INSPECT SYSTEM CIRCUIT WITH CONNECTOR
DISCONNECTED
(a) Disconnect the connectors from the computer, in-
spect at the wire harness side connector.
If the circuit is not as specified, check and repair or re-
place the trouble part shown in the table above.
(b) Connect the connectors, and install the comput-
er cover.
Ignition switch off and brake pedal depressed
Engine running and PKB lever returned Ignition switch off and brake pedal returned
Ignition switch on and PKB lever pulled
Parking broke switch,
level warning switchStop light switch,
stop light Voltage or
Resistance Value
Check connector,
wiring harness
Front RH speed
sensor
FrontrH speed
sensor Ts connector,
wiring harness
Rear RH speed
sensor
Rear RH speed
sensor
Rear LH speed
sensorRear LH speed
sensor Ts connector shorted
Ignition switch offIgnition switch off
Ignition switch off
Ignition switch off Ignition switch off Tester Connection
Ignition switch offIgnition switch off
Ignition switch off
Ignition switch off Ignition switch off Ignition switch off
Ignition switch offIgnition switch off
Ignition switch onBattery voltage
No continuity
Battery voltage
0.85 ± 1.30 k fl
0.85± 1.30k
Battery voltage
Wiring harnessWiring harness
Wiring harness Battery voltage
0.85 ± 1.50 k
0.85 ± 1.50 k

No continuityNo continuity
No continuityNo continuityNo continuityTrouble Part
65±100

ECU±IG fuse Chrak Item
50±80

About 6
ContinuityResistance
Resistance
About 5
ResistanceAbout 6 0
Resistance
ResistanceAbout 6

ResistanceContinuity Resistance
Resistance
ResistanceContinuity
ResistanceAbout 6

ResistanceContinuity
Continuity
Continuity
ContinuityContinuity Continuity
Continuity Continuity
About 0 v
Continuity Continuity
Continuity
Continuity
FOG fuse Condition
ActuatorActuator
Actuator Voltage
VoltageVortege
Actuator Voltage
± BRAKE SYSTEMAnti±lock Brake System (A.B.S.)BR±103

The ER system is composed of there basic sub±systems: Fuel, Air Induction and Electronic Control Systems.
FUEL SYSTEM
Fuel is supplied under constant pressure to the EFI injectors by an electric fuel pump. The injectors inject a
metered quantity of fuel into the intake manifold in a accordance with signals from the ECU (Electronic Control
Unit).
AIR INDUCTION SYSTEM
The air induction system provides sufficient air for engine operation.
ELECTRONIC CONTROL SYSTEM
The Camry 3S±FE and 2V1±FE engines are equipped with a Toyota Computer Control System (TCCS) which
centrally controls the EFI, ESA, ISC, Diagnosis systems etc. by means of an Electronic Control Unit (ECU±
formerly ER computer) employing a microcomputer.
By means of the ECU, the TCCS controls the following functions:
1. Electronic Fuel Injection (EFI)
The ECU receives signals from various sensors indicating changing engine operation conditions such as:
Intake air volume
Intake air temperature
Coolant temperature
Engine rpm
Acceleration/deceleration
Exhaust oxygen content etc.
The signals are utilized by the ECU to determine the injection duration necessary for an optimum air±fuel ratio.
2. Electronic Spark Advance (ESA)
The ECU is programmed with data for optimum ignition timing under any and all operating conditions.
Using data provided by sensors which monitor various engine functions (rpm, coolant temperature, etc.), the
microcomputer (ECU) triggers the spark at precisely the right instant. (See IG section)
3. Idle Speed Control (ISC)
The ECU is programmed with target idling speed values to respond to different engine conditions (coolant
temperature, air conditioner ON/OFF, etc.). Sensors transmit signals to the ECU which control the flow of air
through the by±pass of the throttle valve and adjust idle speed to the target value. (See page FI±45,115
or 62, 117)
4. Diagnosis
The ECU detects any malfunctions or abnormalities in the sensor network and lights a ºCHECKº engine warn-
ing light on the instrument panel. At the same time, the trouble is identified and a diagnosis code is recorded
by the ECU. The diagnosis code can be read by the number of blinks of the ºCHECKº engine warning light
when terminals TE1 and E1 are connected. The diagnostic codes are refer to the later page.
(See page FI±25 or 27)
5. Fail±safe Function
In the event of the sensor malfunctioning, a back±up circuit will take over to provide minimal drivability, and
the ºCHECKº engine warning light.
± EFI SYSTEMSystem DescriptionFI±4

TROUBLESHOOTING
TROUBLESHOOTING HINTS
1. Engine troubles is usually not caused by the EFI system.
When troubleshooting, always first check the condition of
the other systems.
(a) Electronic source
wBattery
wFusible links
wFuses
(b) Body ground
(e) Fuel supply
wFuel leakage
wFuel filter
wFuel pump
(d) Ignition system
wSpark plugs
wHigh±tension cords
wDistributor
wIgnition coil
wIgniter
(e) Air induction system
wVacuum leaks
(f) Emission control system
wPCV system
wEGR system
(g) Others
wIgnition timing (ESA system)
wdle speed (ISC system)
wetc.
2. The most frequent cause of problems is simply a bad contact
in wiring connectors. Always check that connections are
secure.
When inspecting the connector, pay particular attention to
the following points:
(a) Check to see that the terminals are not bent.
(b) Check to see that the connector is pushed in completely and
locked.
(e) Check to see that there is no signal change when the con-
nector is slightly tapped or wiggled.
3. Troubleshoot sufficiently for other causes before replacing
the ECU, as the ECU is of high quality and it is expensive.
± EFI SYSTEMTroubleshootingFI±10

1. Spark plugs
2. Compression pressure
Minimum: 10.0 kg/cm 2
(142 psi, 981 kPa)
at 250 rpm
3. Valve clearance
Standard:
3F±FE IN 0.19 ± 0.29 mm
(0.007 ± 0.011 in.)
EX 0.28 ± 0.38 mm
(0.011 ± 0.015 in.)
2VZ±FE IN 0.13 ± 0.23 mm
(0.005 ± 0.009 in.)
EX 0.27± 0.37 mm
(0.011 ± 0.015 in.)
1. Wiring connection
2. Power to ECU
(1) Fusible link(s)
(2) Fuse(s)
(3) ER main relay (See page FI±121)
3. Air flow meter (See page FI±104)
4. Water temp. sensor (See page FI±125)
5. Air temp. sensor (See page FI±104j
6. Injection signal circuit
(1) Injector wiring
(2) ECU (See page FI±130) CHECK IGNITION TIMING
1. Connect terminals TE1 and E1 of the check connector.
2. Check ignition timing.
Standard: 10° BTDC @ idle
CHECK SPARK PLUGS
Standard: 1.1 mm (0.043 in.)
HINT: Check compression pressure and
valve clearance if necessary.
CHECK EFI ELECTRONIC CIRCUIT USING
VOLT/OHMMETER
(See page FI±31)1. Cold start injector (See page FI±78 or 81)
2. Cold start injector time switch
(See page FI±124)
1. Fuel pump (See page FI±68)
2. Fuel filter
3. Fuel pressure regulator
(See page FI±84 or 86) CHECK COLD START INJECTOR
(See page FI±78 or 81)
OK CONTINUED FROM PAGE FI±13
CHECK FUEL PRESSURE
(See page FI±70)Ignition timing ± Adjust
(See page IG±17 or 21)
CHECK INJECTORS
(See page FI±88 or 93)Injection condition
BADBAD
BAD BAD
± EFI SYSTEMTroubleshootingFI±14

SYMPTOM ± HIGH ENGINE IDLE SPEED (NO DROP)
HINT (3S±FE): Disconnecting the battery will cause the idling speed data in the ISC to be returned to the initial
idling speed, causing the idling speed to rise above 700 rpm. should this happen, either carry out a driving test,
including stop±go several times at a speed above 10 km/h, or start the engine, idle for 30 seconds and then turn
the engine off repeatedly. By doing this, idle data will be stored in the ISC and the idle rpm will be at specified
value.
1. Spark plugs
2. Compression pressure
Minimum: 10.0 kg/cm2
(142 psi, 981 kPa)
at 250 rpm
3. Valve clearance
Standard:
3F±FE IN 0.19 ± 0.29 mm
0.007 ± 0.011 in.)
EX 0.28 ± 0.38 mm
(0.011 ± 0.015 in.)
2VZ±FE I N 0.13 0.23 mm
(0.005 ± 0.009 in.)
EX 0.27± 0.37 m m
(0.011 0.015 in.)
1. Wiring connection
2. Power to ECU
(1) Fusible link(s)
(2) Fuse(s)
(3) ER main relay (Seepage FI±121)
3. Air flow meter (See page FI±104)
4. Water temp. sensor (See page FI±125)
5. Air temp. sensor (See page FI±104)
6. Injection signal circuit
(1) Injector wiring
(2) ECU (See page FI±I30)
7. Oxygen sensor(s)
(See page FI±129 or 131) CHECK SPARK PLUGS
Standard: 1.1 mm (0.043 in.)
HINT: Check compression pressure and valve
clearance if necessary.
CHECK EFI ELECTRONIC CIRCUIT USING
VOLT/OHMMETER
(See page FI±31 )1. Cold start injector (See page FI±78 or 81)
2. Cold start injector time switch
(See page FI±124)
t . Fuel pump (See page FI±68)
2. Fuel filter
3. Fuel pressure regulator
(See page FI±84 or 86) CHECK COLD START INJECTOR
(See page FI±78 or 81)
CHECK FUEL PRESSURE
(See page FI±70)
OK CONTINUED FROM PAGE FI±15
CHECK INJECTORS
(See page FI±88 or 93)Injection condition
BADBAD
BAD
BAD
± EFI SYSTEMTroubleshootingFI±16

1. Wiring connection
2. Power to ECU
(1) Fusible link(s)
(2) Fuse(s)
(3) ER main relay (See page FI±121)
3. Air flow meter (See page FI±104)
4. Water temp. sensor (See page FI±125)
5. Air temp. sensor (See page FI±104)
6. Injection signal circuit
(1) Injector wiring
(2) ECU (See page FI±130)CHECK EFI ELECTRONIC CIRCUIT USING
VOLT/OHMMETER
(See page FI±31)
1. Fuel pump (See page FI±68)
2. Fuel filter
3. Fuel pressure regulator
(See page FI±84 or 86) 1. Wiring connection(s) .
2. ISC valve (See page FI±116 or 118)
3. Air conditioner switch
CHECK DIAGNOSIS SYSTEM
Check for output of diagnosis code.
(See page FI±22)
CHECK THROTTLE POSITION SENSOR
(See page FI±105, 110 or 112) CHECK THROTTLE OPENER SYSTEM
(3S±FE only)
CHECK AIR CONDITIONER IDLE±UP
CIRCUIT
CHECK COLD START INJECTOR
(See page FI±78 or 81) CHECK FUEL PRESSURE
(See page FI±74)Diagnostic code(s) (See page FI±25 or 27)
Injector(s) Leakage, Injection quantityAir valve for air conditioner ± Leakage
CHECK INJECTORS
(See page FI±88 or 93) CHECK ACCELERATOR LINKAGE
CHECK ISC SYSTEMMalfunction
code(s)
Cold start injectorLinkage ± Stuck
Throttle opener
Throttle body
Normal code
BADBAD
BAD
BADBADBADBAD
BADBAD
± EFI SYSTEMTroubleshootingFI±17

(CALIF.)
wWhen air±fuel ratio feed±
back correction value or adap-
tive control value continues at
the upper (lean)
or lower (rich) limit for a certain
period of time or adaptive con-
trol value is not renewed for a
certain period of time.
wWhen feedback frequency of
air±fuel ratio feed±
back correction or adaptive
control is abnormally
high during feedback condition.
(Others)
wOxygen sensor outputs a lean
signal continuously for several
seconds during air±fuel ratio
feedback correction.
wOpen circuit in oxygen sensor
signal (OX).wWater temp. sensor
wInjector circuit
wInjector
wFuel line pressure
wAir flow meter
wAir intake system
wOxygen sensor circuits
wOxygen sensors
wIgnition system
wECU During air±fuel ratio feedback
correction, voltage output from the
main oxygen sensor does exceed a
set value on the lean side and the
rich side continuously for a certain
period.
Water temp. sensor
wInjector circuit
wInjector
wFuel line pressure
wAir flow meter
wCold start injector
wECU wMain oxygen heater circuit
wMain oxygen sensor heater
wECU wIgniter and ignition coil circuit
wIgniter and ignition coil
wECU
wIntake air temp. sensor circuit
wIntake air temp. sensor
wECU Open or short circuit in main oxygen
sensor heater signal
(HT).No NE signal to ECU when the en-
gine speed is above 1,000
rpm.wDistributor circuit
wDistributor
wStarter signal circuit
wECU
wMain oxygen sensor circuit
wMain oxygen sensor
wECU No NE or G signal to ECU
within 2 seconds after engine has
been cranked.
wWater temp. sensor circuit
wWater temp. sensor
wECU
DIAGNOSTIC CODES (2VZ±FE)
Open or short circuit in water temp.
sensor signal (THA).
Open or short circuit in intake air
temp. sensor signal (THA) This appears when none of the oth-
er codes are identified.
wDistributor circuit
wDistributor
wECU
No IGF signal to ECU FI±8
times in succession.
Intake air
Temp. Sensor
Signal
Air±fuel Ratio
Lean
Malfunction Number of
Check engine
blinks
Air±fuel Ratio
Rich
MalfunctionMain oxygen
Sensor Heater
SignalECT control program faulty.
Main oxygen
Sensor Signal
Water temp.
Sensor SignalECT Control
Signal
*CALIF. only Ignition
SignalTrouble area
RPM Signal
RPM SignalDiagnosisSee
page Code
No.System
Normal
wECU
FI±60FI±66
FI±59FI±62IG±4
± EFI SYSTEMDiagnosis SystemFI±27