2001 TOYOTA SEQUOIA Page 18

I28847
RrSG
RrTEI21 Integration Control and Panel:
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2331
2525 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals RrTE and RrSG of integration control and pan-
el.
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 RrTE and RrSG
of the integration control and panel connector at each
temperature.
OK:
Voltage :
at 0°C (32°F) : 2.0 to 2.4 V
at 15°C (59°F) : 1.4 to 1.8 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 DTC 17 is displayed, replace integration control and panel.

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.

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.

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.

I05252
21
N02774
0.2 V/Din.
LOCK IN signal waveform
0 V
20 msec/Division (Idling)
DI±2340
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2534 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check compressor.
PREPARATION:
(a) Check and adjust compressor drive belt tension (See page AC±15).
CHECK:
(a) Check that the compressor does not lock when starting the engine and turning the A/C switch on.
OK: Cooler compressor assy does not lock during operation
HINT:
If the compressor drive belt slips when the A/C switch is on, the magnet clutch seems to be locked.
If the condition continues for more than 3 seconds, the A/C amplifier turns off the magnet clutch for compres-
sor drive belt protection.
NG Replace compressor.
OK
2 Check compressor lock sensor.
PREPARATION:
Disconnect the compressor connector.
CHECK:
Measure the resistance between terminals 1 and 2 of the com-
pressor lock sensor connector.
OK:
Resistance : 65 to 125 W at 20°C (68 °F)
Reference: Inspection using oscilloscope
During cranking or idling, measure the voltage between termi-
nals LOCK and SG±TAM of the integration control and panel.
HINT:
The correct waveform appears as shown in the illustration on
the left.
NG Replace compressor.
OK

± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2341
2535 Author: Date:
2005 SEQUOIA (RM1146U)
3 Check harness and connector between compressor lock sensor and integration
control and panel (See page IN±24).
NG Repair or replace harness or connector.
OK
Replace integration control and panel.