2001 TOYOTA SEQUOIA air conditioning

N16207
Thermometer
Ice
More than
10 cm (3.94in.)1
2
I28971Temperature Resistance (kW)
9.0 10.0
8.0
5.07.0
4.0
2.0 3.0
0.0
14 32 50 68 86 ±10 0 10 20 30
(F) (C) 6.0
1.0
DI±2332
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2526 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check rear evaporator temperature sensor.
PREPARATION:
Remove the rear evaporator temperature sensor (See page
AC±42).
CHECK:
Measure the resistance between terminals 1 and 2 of the evap-
orator temperature sensor connector at each temperature.
OK:
Tester connectionConditionSpecified condition
1±2±10C (14F)7.40 to 9.20 kW
1±2±5C (23F)5.65 to 7.00 kW
1±20C (32F)4.35 to 5.40 kW
1±25C (41F)3.40 to 4.20 kW
1±210C (50F)2.68 to 3.30 kW
1±215C (59F)2.10 to 2.60 kW
1±220C (68F)1.66 to 2.10 kW
1±225C (77F)1.32 to 1.66 kW
1±230C (86F)1.05 to 1.35 kW
NOTICE:

Even slightly touching the sensor may change the re-
sistance value. Be sure to hold the connector of the
sensor.

When measuring, the sensor temperature must be
the same as the ambient temperature.
HINT:
As the temperature increases, the resistance decreases (see
the graph on the left).
NG Replace rear evaporator temperature sensor.
OK
3 Check harness and connector between rear evaporator temperature sensor and
integration control and panel (See page IN±35).
NG Repair or replace harness or connector.
OK
Replace integration control and panel.

I24455
A31
A/C Room Temp.
Sensor (Rear)
2
SG±RrTRRrTR Integration Control and Panel
14 13
I22
I22 GR±R B
1 w/ Rear A/C:
GR±R
R±Y R±YJ31
E J32F
AJ/C
J31 J32
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2333
2527 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 19 Rear Room Temperature Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the temperature inside the cabin and sends the appropriate signals to the integration
control and panel.
DTC No.Detection ItemTrouble Area
19Open or short in rear room temperature sensor circuit.

Rear room temp. sensor

Harness or connector between rear room temp. sensor and
integration control and panel

Integration control and panel
WIRING DIAGRAM
DIDKX±01

I28847
RrTR SG±RrTRI22 Integration Control and Panel:
DI±2334
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2528 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals RrTR and SG±RrTR of integration control and
panel.
PREPARATION:
Remove the integration control and panel with connectors still
connected.
CHECK:
(a) Turn the ignition switch to ON.
(b) Measure the voltage between terminals RrTR and SG±
RrTR of the integration control and panel connector at
each temperature.
OK:
Voltage :
at 25°C (77°F) : 1.8 to 2.2 V
at 40°C (104°F) : 1.2 to 1.6 V
HINT:
As the temperature increases, the voltage decreases.
NG Go to step 2.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±2304). How-
ever, if DTC19 is displayed, replace integration control and panel.

I08309
21
I28970
Resistance (kW)
Temperature
4.0
2.0 3.5
1.5
0.0
10 3.0
1.0 2.5
0.5
20 30 40 5060
68 86 104 122140
(C)
(F) 50
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2335
2529 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check rear room temperature sensor.
PREPARATION:
Disconnect the rear room temperature sensor connector.
CHECK:
Measure the resistance between terminals 1 and 2 of the room
temperature sensor connector at each temperature.
OK:
Tester connectionConditionSpecified condition
1±210C (50F)3.00 to 3.73 kW
1±215C (59F)2.45 to 2.88 kW
1±220C (68F)1.95 to 2.30 kW
1±225C (77F)1.60 to 1.80 kW
1±230C (86F)1.28 to 1.47 kW
1±235C (95F)1.00 to 1.22 kW
1±240C (104F)0.80 to 1.00 kW
1±245C (113F)0.65 to 0.85 kW
1±250C (122F)0.50 to 0.70 kW
1±255C (131F)0.44 to 0.60 kW
1±260C (140F)0.36 to 0.50 kW
NOTICE:

Even slightly touching the sensor may change the re-
sistance value. Be sure to hold the connector of the
sensor.

When measuring, the sensor temperature must be
the same as the ambient temperature.
HINT:
As the temperature increases, the resistance decreases (see
the graph on the left).
NG Replace rear room temperature sensor.
OK
3 Check harness and connector between rear room temperature sensor and in-
tegration control and panel (See page IN±35).
NG Repair or replace harness or connector.
OK
Replace integration control and panel.

Resistance of photo diode
High
Low
Weak
Strong
Strength of solar radiation
I28834
A15
Solar
Sensor
TS 21 Integration Control and Panel
14S5±TS
I20 B
LG 1
2
I20 DI±2336
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2530 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 21 Solar Sensor Circuit
CIRCUIT DESCRIPTION
A photo diode in the solar sensor detects solar radiation and
sends signals to the integration control and panel.
DTC NoDetection ItemTrouble Area
21
Open or short in solar sensor circuit.
Note that output of diagnostic trouble code 21 is not abnormal
when the sensor is not receiving solar radiation.
Solar sensor

Harness or connector between solar sensor and integration
control and panel

Integration control and panel
WIRING DIAGRAM
DI3FB±11

I28847
TS
S5±TRI20 Integration Control and Panel:
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2337
2531 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals TS and S5±TS of integration control and panel.
PREPARATION:
Remove the integration control and panel with connectors still
connected.
CHECK:
(a) Turn the ignition switch to ON.
(b) Measure the voltage between terminals TS and S5±TS of
the integration control and panel connector when the so-
lar sensor is subjected to an electric light, and when the
sensor is covered by a cloth.
OK:
ConditionVoltage
Move the light away from the sensorVoltage increases
Move the light closer to the sensorVoltage decreases
HINT:
Use an incandescent lamp for inspection. Bring it within 30 cm
(11.8 in.) of the solar sensor.
NG Go to step 2.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±2304). How-
ever, if DTC 21 is displayed, replace integration control and panel.

I0830812
DI±2338
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2532 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check solar sensor.
PREPARATION:
Remove the solar sensor.
CHECK:
(a) Cover the sensor with a cloth.
(b) Measure the resistance between terminals 1 and 2 of the
solar sensor connector.
HINT:
Connect the positive (+) lead of the ohmmeter to terminal 2 and
the negative (±) lead to terminal 1 of the solar sensor.
OK:
Tester connectionConditionSpecified condition
A15±1 ± A15±2Sensor is subject to elec-
tric lightExcept 8 W
A15±1 ± A15±2Sensor is covered with a
cloth8 W (No continuity)
NOTICE:
The connection procedure for using a digital tester such as
an TOYOTA electrical tester is shown above. When using
an analog tester, connect the positive (+) lead to terminal
1 and negative (±) lead to terminal 2 of the A/C solar sensor.
HINT:

As the inspection light is moved away from the sensor, the
voltage increases.

Use an incandescent lamp for inspection. Bring it within
30 cm (11.8 in.) of the A/C solar sensor.
NG Replace solar sensor.
OK
3 Check harness and connector between solar sensor and integration control and
panel (See page IN±35).
NG Repair or replace harness or connector.
OK
Replace integration control and panel.

I28835
24
Y±B W±R
A3
A/C Magnetic Clutch
and Lock Sensor 2
1IG4
SG±TAM Integration Control
and Panel
13
I19LOCK
20
I19 Y±B W±R
J14
J/C
AA 23
Y±B
IG4
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2339
2533 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 22 Compressor Lock Sensor Circuit
CIRCUIT DESCRIPTION
This sensor sends 1 pulse per engine revolution to the integration control and panel.
If the compressor speed divided by the engine speed is smaller than a predetermined value, the integration
control and panel turns the compressor OFF. The indicator flashes at about 1 second intervals.
DTC No.Detection ItemTrouble Area
22
All conditions below are detected for 3 sec. or more
(a) Engine speed: 450 rpm or more
(b) Ratio of engine to compressor speed deviates 20% or more
in comparison to normal operation.

Compressor drive belt

Compressor lock sensor

Compressor

Harness or connector between compressor lock sensor and
integration control and panel

Integration control and panel
WIRING DIAGRAM
DIDKY±01