Page 1753 of 4323
DI3CI±19
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±1551
1745 Author: Date:
2005 SEQUOIA (RM1146U)
CIRCUIT INSPECTION
DTC P0500/21 Vehicle speed sensor circuit malfunction
DTC P0503/23 Vehicle speed sensor circuit malfunction
CIRCUIT DESCRIPTION
See page DI±278.
DTC No.DTC Detection ConditionTrouble Area
P0500/21
This trouble code is output when the vehicle speed signal from
the vehicle speed sensor is cut for 0.14 sec. or more while the
cruise control is in operation.Vehicle speed sensor
Vehicle speed sensor signal circuit
ECM
P0503/23
Momentary interruption and noise are detected when a rapid
change of vehicle speed occurs while the cruise control is in
operation.Vehicle speed sensor
Vehicle speed sensor signal circuit
ECM
WIRING DIAGRAM
See page DI±278.
INSPECTION PROCEDURE
See page DI±278.
Page 1754 of 4323

I24840
Battery 117
1E
AM2
1 2W±RI18
Ignition SW
B±R
IG2
85E4ECM
ST1± 1
STOP16
5 S14
Stop Light SW
7G±Y
3
6E4STP
1C B±O
3
F10 FL Block
ALT IGN1
B B
W
1F 1L1
2D 2C15
W±RAM2
ST2
1C2
1J 2
4A2 B±OW4
2G±Y
Instrument Panel J/B
Sub J/B No. 4
Engine Room J/B
Instrument Panel J/B4L±B Sub J/B No. 4
4D1
1
4A4E DI±1552
± DIAGNOSTICSCRUISE CONTROL SYSTEM
1746 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0571/52 Stop light switch circuit malfunction
CIRCUIT DESCRIPTION
When the brake pedal is depressed, the stop light switch assy sends a signal to the ECM. When the ECM
receives this signal, it cancels the cruise control.
Fail±safe function operates to enable normal driving even if there is a malfunction in the stop light signal
circuit.
The cancel condition occurs when positive battery voltage is applied to terminal STP.
When the brake is applied, battery positive voltage is normally applied to terminal STP of the ECM through
the STOP fuse and the stop light switch assy, and the ECM turns the cruise control off.
DTC No.DTC Detection ConditionTrouble Area
P0571/52Stop light switch does not turn off even once the vehicle is
drivenStop light switch assy
Stop light switch assy circuit
ECM
WIRING DIAGRAM
DIAB6±05
Page 1755 of 4323

± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±1553
1747 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
When using the hand±held tester, start the inspection from step 1 and when not using the hand±held tester,
start from step 2.
1 Read value on hand±held tester.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position, and turn the hand±held tester main switch on.
(c) Select the item ºSTP LIGHT SW2 Mº, ºSTP LIGHT SW2 Sº and ºSTP LIGHT SW1 Sº in the DATA LIST,
and read its value displayed on the hand±held tester.
CHECK:
Check that the stop lights come on when the brake pedal is depressed, and go off when the brake pedal
is released.
CCS (ECM):
ItemMeasurement Item
/Display (Range)Normal ConditionDiagnostic Note
STP LIGHT SW2 MStop light SW signal (Main CPU)
/ON or OFFON: Brake pedal depressed
OFF: Brake pedal released±
STP LIGHT SW2 SStop light SW signal (Sub CPU)
/ON or OFFON: Brake pedal depressed
OFF: Brake pedal released±
STP LIGHT SW1 SStop light SW signal (Sub CPU)
/ON or OFFON: Brake pedal depressed
OFF: Brake pedal released±
OK:
When the brake pedal is operated, the normal conditions listed above are shown on the display.
RESULT:
NGA
OK (When troubleshooting according to the PROBLEM SYMPTOMS TABLE)B
OK (When troubleshooting according to the DTC chart)C
B Proceed to next circuit inspection shown in
problem symptoms table (See page DI±1541).
C Replace ECM (See page IN±35).
A
Page 1756 of 4323
I21525
Pushed in Free Stop Light Switch:
DI±1554
± DIAGNOSTICSCRUISE CONTROL SYSTEM
1748 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check operation of stop light.
CHECK:
Check that stop lights come on when the brake pedal is depressed, and go off when the brake pedal is re-
leased.
OK:
The stop lights operate normally.
OK Go to step 5.
NG
3 Inspect stop light switch assy.
PREPARATION:
Disconnect the stop light switch assy connector.
CHECK:
Measure the resistance according to the value(s) in the table
below.
OK:
Switch conditionTester connectionSpecified condition
Switch pin free1 ± 4Below 1 W
Switch pin free2 ± 310 kW or higher
Switch pin pushed in1 ± 410 kW or higher
Switch pin pushed in2 ± 3Below 1 W
NG Replace stop light switch assy.
OK
Page 1757 of 4323

I28460
Wire Harness View:
E4
STP ST1±
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±1555
1749 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check harness and connector (Stop light switch ± battery).
CHECK:
Measure the voltage according to the value(s) in the table below.
OK:
Tester connectionConditionSpecified condition
S14±4 ± Body groundAlways10 to 14 V
S14±2 ± Body groundIgnition SW ON10 to 14 V
NG Repair or replace harness or connector.
OK
5 Check voltage between terminals STP and ST1± of ECM connector and body
ground.
PREPARATION:
(a) Reconnect the stop light switch connector.
(b) Disconnect the ECM connector.
(c) Turn the ignition switch to the ON position.
CHECK:
Measure the voltage according to the value(s) in the table be-
low.
OK:
Tester connection
(Symbol)ConditionSpecified condition
E4±15 (STP) ±
Body groundBrake pedal depressed10 to 14 V
E4±15 (STP) ±
Body groundBrake pedal releasedBelow 1 V
E4±16 (ST1±) ±
Body groundBrake pedal depressedBelow 1 V
E4±16 (ST1±) ±
Body groundBrake pedal released10 to 14 V
NG Repair or replace harness or connector.
OK
Replace ECM (See page IN±35
).
Page 1758 of 4323
DI±1556
± DIAGNOSTICSCRUISE CONTROL SYSTEM
1750 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0607/54 Input signal circuit malfunction
CIRCUIT DESCRIPTION
This DTC indicates the internal abnormalities of the ECM.
DTC No.Detection ItemTrouble Area
P0607/54
The ECM has a supervisory CPU and a control ECU inside.
When each input STP signal is different for 0.15 sec. or more,
this trouble code is output.
This trouble code is output after 0.4 sec. has passed from the
time the cruise cancel input signal (STP input) is input into the
ECM.
ECM
HINT:
The ECM receives signals from each sensor to control all the functions of the cruise control with the micro-
computer.
When a trouble code is detected, fail safe remains on until the ignition switch is turned off.
INSPECTION PROCEDURE
Replace ECM (See page IN±35).
DIAB7±04
Page 1759 of 4323
I28462
Combination Meter
Instrument Panel J/B
I18
Ignition SWEngine Room J/BPIECM
B±O LG±R
Cruise
W±R
Battery
IG2 B±R24
32
1H 1C
AM2
62
1 IGN1
1C6
7C5 E518
1C 1J
2C2D
W±R
5
AM2B 11
B54F10
FLB
± DIAGNOSTICSCRUISE CONTROL SYSTEM
DI±1557
1751 Author: Date:
2005 SEQUOIA (RM1146U)
CRUISE main indicator light circuit
CIRCUIT DESCRIPTION
The CRUISE main indicator light comes on while the cruise control system is in operation and blinks when
there are any problems with the system.
DTCs can be read by counting the number of times the CRUISE main indicator light blinks.
WIRING DIAGRAM
DIDF3±01
Page 1760 of 4323

DI±1558
± DIAGNOSTICSCRUISE CONTROL SYSTEM
1752 Author: Date:
2005 SEQUOIA (RM1146U)
INSPECTION PROCEDURE
HINT:
When using the hand±held tester, start the inspection from 1 and when not using the hand±held tester, start
from step 2.
1 Read value on hand±held tester.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to the ON position and turn the hand±held tester main switch on.
(c) Select the item below in the ºDATA LISTº, and read the display on the hand±held tester.
CHECK:
Check that the CRUISE main indicator light comes on when the cruise main switch is ON, and goes off when
the cruise main switch is OFF.
CCS (ECM):
ItemMeasurement Item
/Display (Range)Normal ConditionDiagnostic Note
CCS INDICATORCruise indicator signal (Main CPU)
/ON or OFFON: ºCRUISE main indicatorº ON
OFF: ºCRUISE main indicatorº
OFF
±
CCS INDICATOR SCruise indicator signal (Sub CPU)
/ON or OFFON: ºCRUISE main indicatorº ON
OFF: ºCRUISE main indicatorº
OFF
±
OK:
When the cruise control main switch is operated, the normal conditions listed above are shown
on the display.
NG Go to step 2.
OK
Proceed to next circuit inspection shown in
problem symptoms table
(See page DI±1541).