TOYOTA SEQUOIA 2001 Service Repair Manual

DIDKT±01
I25617
A14
A/C Room Temp.
Sensor (Front)
2 1
R±W
SG±TR TR Integration Control and Panel
3
L±W
I20
1
I20
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2319
2513 Author: Date:
2005 SEQUOIA (RM1146U)
CIRCUIT INSPECTION
DTC 11 Front 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
11Open or short in front room temperature sensor circuit.

Front room temp. sensor

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

Integration control and panel
WIRING DIAGRAM

I28847
SG±TR TRI20 Integration Control and Panel:
DI±2320
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2514 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals TR and SG±TR of integration control and pan-
el.
PREPARATION:
Remove integration control and panel with connectors still con-
nected.
CHECK:
(a) Turn the ignition switch to ON.
(b) Measure the voltage between terminals TR and SG±TR
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 DTC 11 is displayed, replace integration control and panel.

I08310
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±2321
2515 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check front room temperature sensor.
PREPARATION:
Disconnect the 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 front room temperature sensor.
OK
3 Check harness and connector between front 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.

I28832
SG±TAM Integration Control
and Panel
20
12
I19 Y±B
IA5
13 A1
A/C Ambient
Temp. SensorY±B
8
TA M LG±B LG±B 1
2
I19 IA5Y±BJ/C
J14 CA
J15 DI±2322
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2516 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 12 Ambient Temperature Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the ambient temperature and sends the appropriate signals to the integration control
and panel.
DTC No.Detection ItemTrouble Area
12Open or short in ambient temperature sensor circuit.

Ambient temp. sensor

Harness or connector between ambient temp. sensor and
integration control and panel

Integration control and panel
WIRING DIAGRAM
DIDKU±01

I28847
SG±TAMTA M I19 Integration Control and Panel:
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2323
2517 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals TAM and SG±TAM 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 TAM and SG±
TAM of the integration control and panel connector at
each temperature.
OK:
Voltage :
at 25°C (77°F) : 1.35 to 1.75 V
at 40°C (104°F) : 0.85 to 1.25 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 12 is displayed, replace integration control and panel.

I08311
2
1
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
DI±2324
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2518 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check ambient temperature sensor.
PREPARATION:
Disconnect the ambient temperature sensor connector.
CHECK:
Measure the resistance between terminals 1 and 2 of the ambi-
ent 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 ambient temperature sensor.
OK
3 Check harness and connector between ambient temperature sensor and integra-
tion control and panel (See page IN±35).
NG Repair or replace harness or connector.
OK
Replace integration control and panel.

I28833
A13
A/C Evaporator
Temp. Sensor
(Front)
12
2 Integration Control and Panel
TE
SG±TE W±GG±B4
I20
I20
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2325
2519 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 13 Front Evaporator Temperature Sensor Cir-
cuit
CIRCUIT DESCRIPTION
This sensor detects the temperature inside the cooling unit and sends the appropriate signals to the integra-
tion control and panel.
DTC No.Detection ItemTrouble Area
13Open or short in front evaporator temperature sensor circuit.

Front evaporator temp. sensor

Harness or connector between front evaporator temp. sensor
and integration control and panel

Integration control and panel
WIRING DIAGRAM
DIDKV±01

I28847
SG±TE TEI20 Integration Control and Panel:
DI±2326
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2520 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check voltage between terminals TE and SG±TE 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 TE and SG±TE
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 13 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
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2327
2521 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check front evaporator temperature sensor.
PREPARATION:
Remove the front evaporator temperature sensor.
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 front evaporator temperature sensor.
OK
3 Check harness and connector between front 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.

I08286
E2
Engine Coolant
Temp. Sensor
1 2Integration Control and Panel
I22 E821
28
E8E2 THWECM
THWO
E5 14
W±R2 G±Y
G±WTW DI±2328
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2522 Author: Date:
2005 SEQUOIA (RM1146U)
DTC 14 Engine Coolant Temperature Sensor Circuit
CIRCUIT DESCRIPTION
This sensor detects the engine coolant temperature and sends the appropriate signals to the integration
control and panel. These signals are used for warm up control when the engine is cold.
DTC No.Detection ItemTrouble Area
14Open or short in engine coolant temperature sensor circuit.

Engine coolant temp. sensor

Harness or connector between engine coolant temp. sensor
and ECM

Harness or connector between ECM and integration control
and panel

ECM

Integration control and panel
WIRING DIAGRAM
DI935±03