2001 TOYOTA SEQUOIA DLC3 Ts

DI3IS±11
I27730
Instrument Panel J/B
Passenger Door ECU
(Power Window Switch) Combination Meter
Sliding Roof ECUDLC3 Body ECU
(Located behind
the instrument panel)
Driver Door ECU
(Power Window
Master Switch)
Back Door ECU
(Located inside the back door trim board) Automatic Light Control Sensor
Memory Seat ECU
& SwitchAirbag
Sensor
Assy
Power Window
Motor Front RH

Limit Switch

Pulse Switch Power Window
Motor Front LH

Limit Switch

Pulse Switch
A/C ECU
(Integration Control and Panel)
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
DI±1907
2101 Author: Date:
2005 SEQUOIA (RM1146U)
PARTS LOCATION

DI±1938
± DIAGNOSTICSMULTIPLEX COMMUNICATION SYSTEM
2132 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Check automatic light control sensor.
Using hand±held tester:
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and hand±held tester main switch ON.
BODY ECU:
ItemMeasurement Item/Display
(Range)Normal ConditionDiagnostic Note
ILLUMINATE RATEIllumination rate information/
MIN: 0 MAX: 99.99Condition value will be displayedNormal value: 0.8 ms to 22.0 ms
CHECK:
The value of the illumination rate should change in the following range when the light sensor is exposed to
the light or covered by a hand.
OK:
0.8 ms to 22.0 ms
HINT:
This is the time to be taken for the light sensor to generate one cycle of frequency according to the brightness.
When not using hand±held tester (See page BE±27):
NG Replace the automatic light control sensor.
OK

DIDKQ±01
D05981DLC3
I15897
Trouble Code Display
I15897DEF. SW
DI±2310
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2504 Author: Date:
2005 SEQUOIA (RM1146U)
DTC CHECK / CLEAR
1. DTC CHECK USING HAND±HELD TESTER
(a) Hook up the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) Read the DTCs following the prompts on the tester
screen.
Refer to the hand±held tester operator's manual for fur-
ther details.
(d) Clear the DTCs.
HINT:
After repairing the malfunctions, clear the DTCs.
(1) Connect the hand±held tester to the DLC3.
(2) Turn the ignition switch to the ON position.
(3) Erase the DTCs following the prompts on the tester
screen.
HINT:
Refer to the hand±held tester operator's manual for further de-
tails.
2. DTC CHECK (SENSOR CHECK)
(a) Perform an indicator check. After the indicator check is
completed, the system enters the DTC check mode auto-
matically (See page DI±2312).
(b) Read the DTC displayed on the panel. Refer to the list of
DTCs on page DI±2317 when reading the DTCs (DTCs
are output on the temperature display.).
If the slower display is desired, press the DEF. SW and
change it to step operation. Each time the Temp. Control
switch is pressed, the display changes by 1 step.

A04550
12345678
9 1 0 111 21 31 41 51 6
DLC3
I15897
AUTO S/W
R/F S/W
AC2163
Blinking Pattern
4 times
1 sec.
1 sec.
ON
OFF
± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2313
2507 Author: Date:
2005 SEQUOIA (RM1146U)
3. CHECK DLC3
The vehicle's ECM uses the ISO 9141±2 communication proto-
col. The terminal arrangement of the DLC3 complies with SAE
J1962 and matches the ISO 9141±2 format.
Symbols (Terminal No.)Terminal DescriptionConditionSpecified Condition
SIL (7) ± SG (5)Bus º+º lineDuring transmissionPulse generation
CG (4) ± Body groundChassis groundAlwaysBelow 1 W
SG (5) ± Body groundSignal groundAlwaysBelow 1 W
BAT (16) ± Body groundBattery positiveAlways11 to 14 V
4. INDICATOR CHECK
(a) Turn the ignition switch on while pressing the A/C control
AUTO switch and R/F SW simultaneously.
(b) Check that all the indicators light up and go off at 1 second
intervals 4 times in succession.
HINT:

After the indicator check is ended, the diagnostic trouble
code check begins automatically.

Press the OFF switch when desiring to cancel the check
mode.

DIDKS±01
DI±2314
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2508 Author: Date:
2005 SEQUOIA (RM1146U)
DATA LIST / ACTIVE TEST
1. DATA LIST
HINT:
From the DATA LIST displayed on the hand±held tester, you can read the values of the displays, sensors,
actuators and so on without part removal. Reading the DATA LIST as the first step of troubleshooting is one
way to shorten labor time.
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) From the display on the tester, select ºDATA LISTº.
AIR CONDITIONING:
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic Note
ROOM TEMP
Room temperature sensor /
min.: ±6.5°C (20.3°F)
max.: 57.25°C (135.05°F)Actual room temperature is dis-
played
Open in the circuit:
±6.5°C (20.3°F)
Short in the circuit:
57.25°C (135.05°F)
AMBI TEMP SENS
Ambient temperature sensor /
min.: ±30.8°C (±23.44°F)
max.: 50.8°C (123.44°F)Actual ambient temperature is dis-
played
Open in the circuit:
±30.8°C (±23.44°F)
Short in the circuit:
50.8°C (123.44°F)
EVAP TEMP
Evaporator temperature sensor /
min.: ±29.7°C (±21.46°F)
max.: 59.55°C (139.19°F)Actual evaporator temperature is
displayed
Open in the circuit:
±29.7°C (±21.46°F)
Short in the circuit:
59.55°C (139.19°F)
SOLAR SENS±DSolar sensor (Driver side) /
min.: 0 max.: 255Increases as brightness increasesOpen in the circuit: 0
Short in the circuit: 255
COOLANT TEMP
Engine coolant temperature /
min.: 1.3°C (34.34°F)
max.: 90.55°C (194.99°F)Actual engine coolant temperature
is displayed while the engine is
warmed up
±
SET TEMP±DSet temperature (Driver side) /
min.: 0 max.: 255Set temperature and displayed
temperature are the same±
ESTIMATE TEMP±D
Estimated temperature (Driver
side) / min.: ±200°C (±328°F)
max.: 200°C (392°F)Damper is at ºMAX. COOLº:
±200°C (±328°F)
Damper is at ºMAX. HOTº:
200°C (392°F)
±
A/M DAMP POS±DAir mix damper position (Driver
side) / min.: ±14% max.: 113.5%
Damper is at ºMAX. COOLº:
±10.0%
Damper is at ºMAX. HOTº:
100.0%
±
A/I DAMP POSAir inlet damper position /
min.: ±9% max.: 109%
Damper is at ºRECIRCULATIONº:
±9%
Damper is at ºFRESHº: 109.0%
Damper is at ºHALF±RECIR-
CULATIONº: 30.0 to 80.0%
Open in the circuit: 50.0%
A/M DAMP TARG±D
Air mix damper target position
(Driver side) /
min.: ±14% max.: 113.5%Damper is at ºMAX. COOLº:
±10.0%
Damper is at ºMAX. HOTº:
100.0%
±
A/I DAMP TARGAir inlet damper target position /
min.: ±9% max.: 109%
Damper is at ºRECIRCULATIONº:
±9%
Damper is at ºFRESHº: 109.0%
Damper is at ºHALF±RECIR-
CULATIONº: 30.0 to 80.0%
Open in the circuit: 50.0%

DI±2316
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2510 Author: Date:
2005 SEQUOIA (RM1146U)
2. ACTIVE TEST
HINT:
Performing the ACTIVE TEST using the hand±held tester allows the relay, VSV, actuator and so on to oper-
ate without part removal. Performing the ACTIVE TEST as the first step of troubleshooting is one way to
shorten labor time.
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position.
(c) From the display on the tester, perform the ºACTIVE TESTº.
AIR CONDITIONING:
ItemTest Details / Display (Range)Diagnostic Note
BLOWER MOTORBlower motor / min.: 0 max.: 31±
AIR MIX DAMP±DAir mix damper (Driver side) / min.: ±14% max.: 113.5%±
A/I DAMP±LINEARAir inlet damper position (Linear) / min.: ±14% max.: 113.5%±
REAR BLOWERBlower motor (Rear) / min.: 0 max.: 31±
AIR MIX DAMP±RAir mix damper (Rear) / min.: ±14% max.: 113.5%±
A/C MAG CLUTCHA/C magnetic clutch relay / OFF, ON±
DEFOGGER RLY±RDefogger relay (Rear) / OFF, ON±

DI±2382
± DIAGNOSTICSAIR CONDITIONING SYSTEM
2576 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
1 Read value of hand±held tester.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tester main SW ON.
CHECK:
Select the item below in the DATA LIST, and read the displays on the hand±held tester.
ENGINE AND ECT / ALL:
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic Note
A/C SIGA/C signal / ON or OFF
A/C SW Pushed: ON

A/C SW Released: OFF±
HINT:
Check with the engine running.
OK:
The display is as specified in the normal condition.
NG Go to step 8.
OK
2 Read value of hand±held tester.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tester main SW ON.
CHECK:
Select the item below in the DATA LIST, and read the displays on the hand±held tester.
ENGINE AND ECT / ALL:
ItemMeasurement Item / Display
(Range)Normal ConditionDiagnostic Note
A/C MAG CLUTCHA/C magnet clutch / ON or OFF
A/C SW ON: ON

A/C SW OFF: OFF±
HINT:
Check with the engine running.
OK:
The display is as specified in the normal condition.
NG Replace ECM (See page SF±80).
OK

± DIAGNOSTICSAIR CONDITIONING SYSTEM
DI±2383
2577 Author: Date:
2005 SEQUOIA (RM1146U)
3 Perform active test by hand±held tester.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch ON and push the hand±held tester main SW ON.
CHECK:
Select the item below in the DATA LIST, and read the displays on the hand±held tester.
AIR CONDITIONING:
ItemTest Details / Display (Range)Diagnostic Note
A/C MAG CLUTCHMagnet clutch relay / OFF, ONOperating sound can be heard
HINT:
Check with the engine running.
OK:
The operation sound of the MG CLT relay can be heard.
NG Go to step 5.
OK
4 Check harness and connector between integration control and panel (ACT termi-
nal) and ECM (ACT terminal) (See page IN±35).
NG Repair or replace harness or connector.
OK
Proceed to next circuit inspection shown in problem symptoms table (See page DI±2304).