TOYOTA CAMRY 2000 Service Repair Manual

Are there any other codes (beside Code 27)
being output?Go to relevant diagnostic trouble
code chart.
DIAGNOSTIC CHART
WIRING DIAGRAM
Replace sub oxygen sensor.YES
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CIRCUIT DESCRIPTION
By a built±in sensor unit, the manifold absolute
pressure sensor detects the intake manifold absolute
pressure as a voltage.
The ECM then determines the basic injection dura±
tion and basic ignition advance angle based on this
voltage.
Since the manifold absolute pressure sensor does
not use the atmospheric pressure as a criterion, but
senses the absolute pressure inside the intake man±
ifold (the pressure in proportion to the preset abso±
lute vacuum O), it is not influenced by fluctuations
in the atmospheric, pressure due to high altitude
and other factors. This permits it to control the air±
fuel ratio at the proper level under all conditions.
If the ECM detect diagnostic trouble code ª31 ª, it operates the fail safe function, keeping the ignition
timing and fuel injection volume constant and making it possible to drive the vehicle.w
Open or short in manifold absolute pressure
sensor circuit.
wManifold absolute pressure sensor.
wECM Open or short in manifold absolute pressure sensor
circuit for 0.5 sec. or more.Diagnostic Trouble Code Detecting Condition Trouble Area
DTC 31 Manifold Absolute Pressure Sensor Circuit
DTC No.
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Check for open and short in harness and
connector between manifold absolute pressure
sensor and ECM.
Check and replace manifold absolute pressure
sensor.When diagnostic trouble code 31 is
displayed, check and replace ECM.
Repair or replace harness or
connector.
DIAGNOSTIC CHART
Check voltage of terminal PIM.Check voltage of terminal VC. Check and replace ECM.
DIA RAMWIRING DIAGRAM
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(1) Remove glove compartment.
(See page EG1±234).
(2) Turn ignition switch on.
Measure voltage between terminals VC and E2 of
engine control module connector.
Voltage: 4.5 ~ 5.5 V Check voltage between terminals VC and E2 of engine control
module connector.
Check and replace engine control module.
INSPECTION PROCEDURE
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Check for open and short in harness and connector between engine
control module and manifold absolute pressure sensor
(See page IN±31).
Turn ignition switch on
Check voltage between terminals PIM and E2 of engine control
module connector.
Check and replace manifold absolute pressure
sensor.When diagnostic trouble code 31 is dis-
played, check and replace engine control
module.
Repair or replace harness or connector. Voltage: 13 ± 3.9 V Measure voltage between terminals PI M
and E2 of engine control module connector.
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CIRCUIT DESCRIPTION
HINT;
wWhen the connector for the throttle position sensor is disconnected, diagnostic trouble code 41
is not displayed. Diagnostic trouble code 41 is displayed only when there is an open or short in
the VTA signal circuit of the throttle position sensor.w
Open or short in throttle position sensor circuit.
wThrottle position sensor.
wECM Open or short in throttle position sensor circuit
for 0.5 sec. or more.Diagnostic Trouble Code Detecting Condition
Trouble Area
DTC 41 Throttle Position Sensor Circuit
DTC No.
The throttle position sensor is mounted in the throttle
body and detects the throttle valve opening angle. When
the throttle valve is fully closed, the I D L contacts in the
throttle position sensor are on, so the voltage at the ter±
minal I D L of the ECM become 0 V. At this time, a voltage
of approximately 0.7 V is applied to the terminal VTA of
the ECM. When the throttle valve is opened, the I D L
contacts go off and thus the power source voltage of
approximately 12 V in the ECM is applied to the terminal
IDL of the ECM. The voltage applied to the terminal VTA
of the ECM increases in proportion to the opening angle
of the throttle valve and becomes approximately 3.2 ±
4.9 V when the throttle valve is fully opened. The ECM
judges the vehicle driving conditions from these signals
input from the terminals VTA and IDL, and uses them as
one of the conditions for deciding the air±fuel ratio cor±
rection, power increase correction and fuel±cut control etc.
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DIAGNOSTIC CHART
HINT: If diagnostic trouble codes ª22º (engine coolant temperature sensor circuit), ª24º (intake air
temperature sensor circuit),ª31º (manifold absolute pressure sensor circuit) and ª41º (throttle posi±
tion sensor circuit) are output simultaneously, E2 (sensor ground) may be open.
Check for open and short in harness and
connector between throttle position sensor and
ECM.Check for momentary interruption
(See page EG1±309).
Adjust or replace throttle position
sensor.
Repair or replace harness or
connector. Check operation for throttle position sensor.Check voltage of throttle position sensor.
WIRING DIAGRAM
Check and replace ECM.
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INSPECTION PROCEDURE
HINT: If diagnostic trouble code ª22º (engine coolant temperature sensor circuit), ª24º (intake air
temperature sensor circuit), ª31º (manifold absolute pressure sensor circuit) and ª41 ª (throttle
position sensor circuit) are output simultaneously, E2 (sensor ground) may be open.
(1) Remove glove compartment.
(See page EG1±234).
(2) Disconnect the vacuum hose from the throt±
tle body, then apply vacuum to the throttle
opener (See page EG1±204).
(3) Turn ignition switch ON.
Measure voltage between terminals VTA, IDL and
E2 of engine control module connector when the
throttle valve is opened gradually from the closed
condition.
Check voltage between terminals VTA, IDL and E2 of engine
control module connector.
The voltage should increase steadily in propor±
tion to the throttle valve opening angle.
Check for momentary interruption
(See page EG1±309).
Throttle Valve
Fully Closed
Fully OpenVTA ± E2 Terminal
IDL ± E2
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(1) Disconnect throttle position sensor connector.
(2) Disconnect the vacuum hose from the throt±
tle body, then apply vacuum to the throttle
opener (See page EG1±204).
Check for open and short in harness and connector between engine
control module and throttle position sensor (See page IN±31).
Resistance between terminals 3 (VTA) and 1
(E2) should increase gradually in accordance
with the throttle valve opening angle.
Adjust or replace throttle position sensor
(See page EG1±209).
Check throttle position sensor.
Check and replace engine control module.Repair or replace harness or connector.
3 (VTA) ± 1 (E2) 2 (IDL) ± 1 (E2)
Throttle Valve
Fully Closed
Fully OpenTerminal
Measure resistance between terminals 3 (VTA), 2
(IDL) and 1 (E2) of throttle position sensor con±
nector when the throttle valve is opened gradu±
ally from the closed condition.
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CIRCUIT DESCRIPTION
The No.1 vehicle speed sensor outputs a 4±pulse signal for every revolution of the rotor shaft,
which is rotated by the transmission output shaft via the driven gear. After this signal is converted
into a more precise rectangular waveform by the waveform shaping circuit inside the combination
meter, it is then transmitted to the ECM. The ECM determines the vehicle speed based on the fre-
quency of these pulse signals.
For M /T
All conditions below are detected continuously
for 8 sec. or more.
(a) No.1 vehicle speed signal: 0 mph (km/h)
(b) Engine speed: Between 3,100 rpm and
5,000 rpm
(c) Engine coolant temp.: 80
C (176
F) or more
(d) Load driving
wWaveform between terminals SPD and E1 when vehicle
speed is approx. 12 mph (20 km/h).
HINT: The greater the vehicle speed, the greater the num±
ber of No.1 vehicle speed sensor signals produced.
For A/T
All conditions below are detected continuously
for 8 sec. or more.
(a) No.1 Vehicle speed signal: 0 mph (km/h)
(b) Engine speed: 3,100 rpm or more
(c) Park/Neutral position switch: OFF
HINT: In test mode, diagnostic trouble code 42 is output when vehicle speed is 3 mph (5 km/h)
or below.
wOpen or short in No.1 vehicle speed sensor
circuit.
wNo.1 vehicle speed sensor.
wCombination meter.
wECM Diagnostic Trouble Code Detecting Condition
Trouble Area
DTC 42 No.1 Vehicle Speed Sensor Signal Circuit
DTC No.
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