2001 TOYOTA AVALON air condition
[x] Cancel search: air conditionPage 780 of 1897
- DIAGNOSTICSAUTOMATIC TRANSAXLE
DI-169
325 Author: Date:
2001 AVALON (RM808U) (c) Stall speed high in R position
Line pressure too low
Direct clutch slipping
1st & reverse brake slipping
O/D clutch slipping
(d) Stall speed high in D and R positions
Line pressure too low
Improper fluid level
O/D one-way clutch not operating properly
(b) Measure the time lag.
When the shift lever is shifted while the engine is idling, there will be a certain time lapse or lag before
the shock can be felt. This is used for checking the conditions of the O/D direct clutch, forward clutch,
and 1st & reverse brake.
NOTICE:
Do the test at normal operating fluid temperature 50 - 80 °C (122 - 176 °F).
Be sure to allow 1 minute interval between tests.
Take 3 measurements and take the average value.
(1) Connect an OBD II scan tool or TOYOTA hand-held tester to DLC3.
(2) Fully apply the parking brake.
(3) Start the engine and check idle speed.
Idle speed: 700 ± 50 rpm (In N position and air conditioner OFF)
(4) Shift the shift lever from N to D position. Using a stop watch, measure the time from when the
lever is shifted until the shock is felt.
Time lag: N " D Less than 1.2 seconds
In the same manner, measure the time lag for N " R.
Time lag: N " R Less than 1.5 seconds
Evaluation (If N " D time or N " R time lag is longer than the specified):
ProblemPossible cause
N " D time lag is longer
Line pressure too low
Forward clutch worn
O/D one-way clutch not operating
N " R time lag is longer
Line pressure too low
Direct clutch worn
1st & reverse brake worn
O/D one-way clutch not operating properly
Page 781 of 1897
DI-170
- DIAGNOSTICSAUTOMATIC TRANSAXLE
326 Author: Date:
2001 AVALON (RM808U)
7. HYDRAULIC TEST
Measure the line pressure.
NOTICE:
Do the test at normal operation fluid temperature 50 - 80 °C (122 - 176 °F).
The line pressure test should always be carried out in pairs. One technician should observe
the conditions of wheels or wheel stoppers outside the vehicle while the other is doing the test.
Be careful to prevent SST's hose from interfering with the exhaust pipe.
(1) Warm up the ATF.
(2) Remove the test plug on the transaxle case front left side and connect SST (See page AX-33
for the location to connect SST).
SST 09992-00095 (09992-00231, 09992-00271)
(3) Fully apply the parking brake and chock the 4 wheels.
(4) Connect an OBD II scan tool or TOYOTA hand-held tester to DLC3.
(5) Start the engine and check idling speed.
(6) Keep your left foot pressing firmly on the brake pedal and shift into D position.
(7) Measure the line pressure when the engine is idling.
(8) Depress the accelerator pedal all the way down. Quickly read the highest line pressure when
engine speed reaches stall speed.
(9) In the same manner, do the test in R position.
Specified line pressure:
ConditionD position kPa (kgf/cm2, psi)R position kPa (kgf/cm2, psi)
Idling401 - 461 (4.1 - 4.7, 58 - 66)804 - 882 (8.2 - 9.0, 117 - 128)
Stall1,138 - 1,236 (11.6 - 12.6, 165 - 179)1,716 - 1,854 (17.5 - 18.9, 249 - 269)
If the measured pressure is not up to the specified value, recheck the throttle cable adjustment and retest.
Evaluation:
ProblemPossible cause
If the measured values at all positions are higher
Throttle cable out of adjustment
Throttle valve defective
Regulator valve defective
If the measured values at all positions are lower
Throttle cable out of adjustment
Throttle valve defective
Regulator valve defective
Oil pump defective
O/D direct clutch defective
If pressure is low in the D position onlyD position circuit fluid leakage
Forward clutch defective
If pressure is low in the R position only
R position circuit fluid leakage
Direct clutch defective
1st & reverse brake defective
Page 865 of 1897
N16045
3
4
- DIAGNOSTICSCRUISE CONTROL SYSTEM
DI-591
747 Author: Date:
2001 AVALON (RM808U)
2 Check cancel switch continuity.
PREPARATION:
(a) Remove steering wheel center pad (See page SR-12).
(b) Disconnect the control switch connector.
CHECK:
Check continuity between terminals 3 and 4 of control switch
connector when cancel switch is held ON and OFF.
OK:
Switch positionTester connectionSpecified condition
OFF3 - 4No continuity
Hold ON3 - 4Continuity
NG Replace control switch.
OK
3 Check harness and connector between cruise control ECU and cancel switch
(See page IN-30).
NG Repair or replace harness or connector.
OK
Check and replace cruise control ECU (See
page IN-30).
Page 907 of 1897
DI07F-09
A06106
B+
Thermister
Power Transister
Platinum Hot Wire
B
Output
Voltage A
FI6929
S05741
- DIAGNOSTICSENGINE
DI-23
179 Author: Date:
2001 AVALON (RM808U)
CIRCUIT INSPECTION
DTC P0100 Mass Air Flow Circuit Malfunction
CIRCUIT DESCRIPTION
The mass air flow meter uses a platinum hot wire. The hot wire air flow meter consists of a platinum hot wire,
thermistor and a control circuit installed in a plastic housing. The hot wire air flow meter works on the principle
that the hot wire and thermistor located in the intake air bypass of the housing detect any changes in the
intake air temperature.
The hot wire is maintained at the set temperature by controlling the current flow through the hot wire. This
current flow is then measured as the output voltage of the air flow meter.
The circuit is constructed so that the platinum hot wire and thermistor provide a bridge circuit with the power
transistor controlled so that the potential of A and B remains equal to maintain the set temperature.
DTC No.DTC Detecting ConditionTrouble Area
P0100Open or short in mass air flow meter circuit with more than 3
sec. engine speed 4,000 rpm or lessOpen or short in mass air flow meter circuit
Mass air flow meter
ECM
If the ECM detects DTC P0100 it operates the fail-safe function, keeping the ignition timing and injection
volume constantly and making it possible to drive the vehicle.
HINT:
After confirming DTC P0100, use the OBD II scan tool or TOYOTA hand-held tester to confirm the mass
air flow ratio from the CURRENT DATA.
Mass Air Flow Value (gm/sec.)Malfunction
0.0Mass air flow meter power source circuit open
VG circuit open or short
271.0 or moreE2G circuit open
Page 908 of 1897
A11668
Engine Room J/B
EFI No.1
2G
2B 2A
2F2
5
1 3
2B-W
4L-O
4 2
EFI No.2 EFI Relay
From BatteryB
Mass Air
Flow Meter3
2 1
EDW-B
R-BECM
E2GVG
E2 R10
19
E5E5
From
Terminal
MREL of
ECM
DI-24
- DIAGNOSTICSENGINE
180 Author: Date:
2001 AVALON (RM808U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand-held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining
whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean
or rich, etc. at the time of the malfunction.
1 Connect OBD II scan tool or TOYOTA hand-held tester, and read value of mass
air flow rate.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the OBD II scan tool or TOYOTA hand-held tester main switch
ON.
(c) Start the engine.
CHECK:
Read the mass air flow rate on the OBD II scan tool or TOYOTA hand-held tester.
RESULT:
Type IType II
Mass Air Flow Rate (gm/sec.)0.0271.0 or more
Type I Go to step 2.
Type II Go to step 5.
Page 911 of 1897
- DIAGNOSTICSENGINE
DI-27
183 Author: Date:
2001 AVALON (RM808U)
DTC P0101 Mass Air Flow Circuit Range/Performance
Problem
CIRCUIT DESCRIPTION
Refer to DTC P0100 on page DI-23.
DTC No.DTC Detecting ConditionTrouble Area
P0101
Conditions (a), (b) and (c) continue 10 sec. or more with en-
gine speed NE < 900: (2 trip detection logic)
(a) Throttle valve fully closed
(b) Mass air flow meter output 2.2 V
(c) THW 70°C
Mass air flow meterP0101
Conditions (a) and (b) continue 10 sec. or more with engine
speed 1,500 rpm or more: (2 trip detection logic)
(a) VTA 0.63 V
(b) Mass air flow meter output 1.06 V
Mass air flow meter
INSPECTION PROCEDURE
HINT:
Read freeze frame data using TOYOTA hand-held tester or OBD II scan tool. Because freeze frame records
the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining
whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean
or rich, etc. at the time of the malfunction.
1 Are there any other codes (besides DTC P0101) being output?
NO Replace mass air flow meter.
YES
Go to relevant DTC chart (See page DI-14).
DI07G-09
Page 912 of 1897
FI4741
Fig. 1
Acceptable
Resistance kW
- 20 0 20 40 60 80 100
(- 4) (32) (68) (104) (140) (176) (212) 30
20
10
5
3
2
1
0.5
0.3
0.2
0.1
Te m p .°C (F°)
DI-28
- DIAGNOSTICSENGINE
184 Author: Date:
2001 AVALON (RM808U)
DTC P0110 Intake Air Temp. Circuit Malfunction
CIRCUIT DESCRIPTION
The intake air temperature sensor is built into mass air flow me-
ter and senses the intake air temperature.
A thermistor built in the sensor changes the resistance value
according to the intake air temperature.
The lower the intake air temperature, the greater the thermistor
resistance value, and the higher the intake air temperature, the
lower the thermistor resistance value (See Fig. 1).
The intake air temperature sensor is connected to the ECM.
The 5 V power source voltage in the ECM is applied to the in-
take air temperature sensor from terminal THA via resistor R.
That is, resistor R and the intake air temperature sensor are
connected in series. When the resistance value of the intake air
temperature sensor changes in accordance with changes in the
intake air temperature, the potential at terminal THA also
changes. Based on this signal, the ECM increases the fuel in-
jection volume to improve driveability during cold engine opera-
tion.
If the ECM detects the DTC P0110, it operates the fail-safe
function in which the intake air temperature is assumed to be
20°C (68°F).
DTC No.DTC Detecting ConditionTrouble Area
P0110Open or short in intake air temp. sensor circuit
Open or short in intake air temp. sensor circuit
Intake air temp. sensor (built into mass air flow meter)
ECM
HINT:
After confirming DTC P0110, use the OBD II scan tool or TOYOTA hand-held tester to confirm the intake
air temperature form the CURRENT DATA.
Temperature DisplayedMalfunction
-40°C ( -40°F )Open circuit
140°C ( 284°F ) or moreShort circuit
DI07H-10
Page 913 of 1897
A00310A09772
5 V
THA
E2
E1 22
18 4
5R Intake Air Temp. Sensor
(Built into Mass Air Flow Meter)ECM
L-B
W
E5 E5
- DIAGNOSTICSENGINE
DI-29
185 Author: Date:
2001 AVALON (RM808U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
If DTCs P0110, P0115, P0120 and P1410 are output simultaneously, E2 (sensor ground) may be open.
Read freeze frame data using TOYOTA hand-held tester or OBD II scan tool. Because freeze frame
records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for
determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel
ratio was lean or rich, etc. at the time of the malfunction.
1 Connect OBD II scan tool or TOYOTA hand-held tester, and read value of intake
air temperature.
PREPARATION:
(a) Connect the OBD II scan tool or TOYOTA hand-held tester to the DLC3.
(b) Turn the ignition switch ON and push the OBD II scan tool or TOYOTA hand-held tester main switch
ON.
CHECK:
Read the temperature value on the OBD II scan tool or TOYOTA hand-held tester.
OK:
Same as actual intake air temperature.
HINT:
If there is open circuit, OBD II scan tool or TOYOTA hand-held tester indicates -40°C (-40°F).
If there is short circuit, OBD II scan tool or TOYOTA hand-held tester indicates 140°C (284°F) or more.
NG -40°C (-40°F) ... Go to step 2.
140°C (284°F) or more ... Go to step 4.
OK
Check for intermittent problems
(See page DI-3).