Page 494 of 4323

DI±292
± DIAGNOSTICSENGINE
486 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0560 System Voltage
MONITOR DESCRIPTION
The battery supplies electricity to the ECM even when the ignition switch is OFF. This electricity allows the
ECM to store data such as DTC history, freeze frame data, fuel trim values, and other data.
If the battery voltage falls below a minimum level, the ECM will conclude that there is a fault in the power
supply circuit. The next time the engine starts, the ECM will turn on the MIL and a DTC will be set.
DTC No.DTC Detecting ConditionTrouble Area
P0560Open in back up power source circuit
Open in back±up power source circuit
EFI fuse
ECM
HINT:
If DTC P0560 present, the ECM will not store another DTC.
MONITOR STRATEGY
Related DTCsP0560System voltage malfunction
Required sensors/componentsECM
Frequency of operationContinuous
Duration3 sec.
MIL operationImmediate (*1)
Sequence of operationNone
*1: The DTC is set immediate. The MIL will be illuminated after the engine starts in the next time.
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever this DTC is
not presentSee page DI±18
Stand±by RAMInitialized
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Battery voltageLess than 3.5 V
DICF7±02
Page 495 of 4323
A05652A18100
Battery2DEFI No. 1
B±Y
E4ECM
BATT 73
2H 1
IA411
B±Y B
F10
Fusible Link
Block 4Engine Room J/B
5
B12
± DIAGNOSTICSENGINE
DI±293
487 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions when
a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was
running or stopped, if the engine was warmed up or not, if the air±fuel ratio was lean or rich, as well as other
data from the time when a malfunction occurred.
1 Check battery voltage.
PREPARATION:
(a) Connect the hand±held tester to the DLC3.
(b) Turn the ignition switch to ON.
(c) Select the item: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / BATTERY VOLTAGE.
CHECK:
Read the battery voltage on the hand±held tester
RESULT:
Battery voltageProceed to
0 VA
Except 0 VB
B Go to step 5.
A
Page 496 of 4323
A21381
Engine Room J/B
EFI No. 1 Fuse
B17411
BATT (+) E6
E4
E1(±)
DI±294
± DIAGNOSTICSENGINE
488 Author: Date:
2005 SEQUOIA (RM1146U)
2 Check EFI No. 1 fuse of engine room J/B.
PREPARATION:
Remove the EFI No. 1 fuse from the engine room J/B.
CHECK:
Check the resistance of the EFI No. 1 fuse.
OK:
Standard: Below 1 W
NG Check for short in all harness and components
connected to EFI No. 1 fuse.
OK
3 Check voltage between terminal BATT and E1 of ECM connector.
CHECK:
Measure the voltage between terminals of the E6 and E4 ECM
connector.
OK:
Standard:
Tester ConnectionSpecified Condition
BATT (E4±3) ± E1 (E6±1)9 to 14 V
OK Check for intermittent problems
(See page DI±11).
NG
Page 497 of 4323
A21381
Engine Room J/B
EFI No. 1 Fuse
B17417
E4
BATT ECM Connector
± DIAGNOSTICSENGINE
DI±295
489 Author: Date:
2005 SEQUOIA (RM1146U)
4 Check for open and short in harness and connector between ECM and EFI No. 1
fuse, EFI No. 1 fuse and battery.
PREPARATION:
(a) Remove the EFI No. 1 fuse from the engine room J/B.
(b) Disconnect the E4 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tor.
OK:
Standard:
Tester ConnectionSpecified Condition
Engine Room J/B (EFI No. 1 fuse
terminal 2) ± BATT (E4±3)Below 1 W
Engine Room J/B (EFI No. 1 fuse
terminal 2) or BATT (E4±3) ±
Body ground
10 kW or higher
NG Repair or replace harness or connector.
OK
5 Check the battery (See page CH±1).
NG Replace battery.
OK
Check and replace engine room J/B.
Page 498 of 4323

DI±296
± DIAGNOSTICSENGINE
490 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0604 Internal Control Module Random Access
Memory (RAM) Error
DTC P0606 ECM/PCM Processor
DTC P0607 Control Module Performance
DTC P0657 Actuator Supply Voltage Circuit / Open
MONITOR DESCRIPTION
The ECM continuously monitors its internal memory status, internal circuits, and output signals to the throttle
actuator. This self±check insures that the ECM is functioning properly. If any malfunction is detected, the
ECM will set the appropriate DTC and illuminate the MIL.
The ECM memory status is diagnosed by internal ºmirroringº of the main CPU and the sub CPU to detect
RAM (Random Access Memory) errors. The two CPUs also perform continuous mutual monitoring.
The ECM sets a DTC if: 1) outputs from the 2 CPUs are different and deviate from the standards, 2) the sig-
nals to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator sup-
ply voltage, and 4) any other ECM malfunction is found.
DTC No.DTC Detecting ConditionTrouble Area
P0604
P0606
P0607
P0657
ECM malfunctionECM
MONITOR STRATEGY
P0604Random access memory (RAM) error
RltdDTCP0606CPU malfunctionRelated DTCsP0607ECM range check
P0657ETCS power supply
Required sensors/componentsECM
Frequency of operationContinuous
DurationWithin 1 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
The monitor will run whenever these
DTCs are not presentSee page DI±18
The typical enabling condition is not avail-
able±
DI3IK±13
Page 499 of 4323

± DIAGNOSTICSENGINE
DI±297
491 Author: Date:
2005 SEQUOIA (RM1146U)
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
P0604:
RAMRAM check failure
P0606:
Either of the following conditions is metCondition 1 or 2
1. Difference between TP of main CPU and TP of sub CPU0.3 V or more
2. Difference between APP of main CPU and APP of sub
CPU0.3 V or more
P0607:
Either of the following conditions is metCondition 1 or 2
1. All of the following conditions are metCondition (a), (b) and (c)
(a) CPU reset1 time or more
(b) Difference between TP and APP learned0.4 V or more
(c) Electronic throttle actuatorOFF
2. CPU reset2 times or more
P0657:
ECTS power supply when ignition switch OFF to ON7 V or more
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester. Freeze frame data records the engine conditions when
a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was
running or stopped, if the engine was warmed up or not, if the air±fuel ratio was lean or rich, as well as other
data from the time when a malfunction occurred.
Replace ECM (See page SF±80).
Page 500 of 4323

DI±298
± DIAGNOSTICSENGINE
492 Author: Date:
2005 SEQUOIA (RM1146U)
DTC P0617 Starter Relay Circuit High
MONITOR DESCRIPTION
While the engine is being cranked, the battery positive voltage is applied to terminal STA of the ECM.
If the vehicle is being driven and the ECM detects the starter control signal (STA), the ECM concludes that
the starter control circuit is malfunctioning. The ECM will turn on the MIL and a DTC is set.
DTC No.DTC Detection ConditionTrouble Area
P0617
When all conditions (a), (b) and (c) are satisfied for 20 seconds
with battery (+B) voltage 10.5 V or more
(a) Vehicle speed 20 km/h (12.4 mph)
(b) Engine revolution 1,000 rpm
(c) STA signal ONPark/neutral position switch
Starter relay circuit
Ignition switch
ECM
MONITOR STRATEGY
Related DTCsP0617Starter signal error
Rid / tMain sensors/componentsStarter signalRequired sensors/componentsRelated sensors/componentsVehicle speed sensor, Engine speed sensor
Frequency of operationContinuous
Duration20 sec.
MIL operationImmediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever this DTC is
not presentSee page DI±18
Battery voltage10.5 V±
Vehicle speed20 km/h (12.4 mph)±
Engine RPM1,000 rpm±
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Starter signalON (at ºmore than 20 km/h (12.4 mph) and more than 1,000 rpmº)
DID8D±01
Page 501 of 4323
A23548
ECM
E4
STAR ACCR
AM28
ED I18
Ignition SWB B
B±W 1C9
620
42 P
1
B±W
B 1
J2
J/C 1
17
B±O
2D
ALTE7 J38
1FGR
W4
ED2 IA1
S3 F10
Fusible
Link Block4
W±R
B±L
Battery 5B
ST 3A
1
StarterST Relay 5
B
12 3
Instrument Panel J/B
12
Engine Room J/B
2C
5 Sub J/B No. 4
P 3A 12A36
ACC CUT Relay
to Audio
J37J/C
C
GR
4 GR
N B±R
B±R
J/C BD
J51 J52B±R
STSW
E6 IG4B
Engine Room R/B No.2
2 B
2 2
2
2 2 B±RB±R RAD No.2
1C
1C
1C
1J 1J1J
1L
1E 3
5
W±L W±R
W±R
2C
2E1
3B±R
3
B1
B±W
W±B 6
A 1
2 3 58
3
J5
J/C 1
1W±B 128 B±R
W±RJ51 BE6 11
STA W±R
21
3
S2W±R4A
4B 19
9 Sub J/B No.4 GR
P1
Park/Neutral
Position SW
AM1ACC
AM2
ST2
ECU±B
SHORT PIN
B 7
B 2AM1
1
STA8
IA5
± DIAGNOSTICSENGINE
DI±299
493 Author: Date:
2005 SEQUOIA (RM1146U)
WIRING DIAGRAM