Page 1329 of 3115

DI-280
- DIAGNOSTICSENGINE
473 Author: Date:
2004 LAND CRUISER (RM1071U)
INSPECTION PROCEDURE
HINT:
Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the
engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help deter-
mine 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.
Hand-held tester:
1 Check operation of stop light.
CHECK:
Check if the stop lights come on and go off normally when the brake pedal is operated and released.
NG Check and repair stop light circuit.
OK
2 Check STOP fuse.
PREPARATION:
Remove the STOP fuse from the cowl side J/B LH.
CHECK:
Check the continuity of the STOP fuse.
OK:
Continuity
NG Check for short in all harness and components
connected to STOP fuse.
OK
3 Check stop light switch (See page BE-50).
NG Replace stop light switch.
OK
Page 1330 of 3115
A19642
Brake Pedal
DepressedBrake Pedal
Release ON
() ()
ST1-(+)E8
E7
E1 (-)
- DIAGNOSTICSENGINE
DI-281
474 Author: Date:
2004 LAND CRUISER (RM1071U)
4 Check STP signal and ST1- voltage.
PREPARATION:
(a) Turn the ignition switch ON.
(b) Select the item ºDIAGNOSIS / ENHANCED OBD II /
DATA LIST / ALL / STOP LIGHT SWº.
CHECK:
Read the signal displayed on the hand-held tester.
OK:
Brake PedalSpecified Condition
DepressedSTP Signal ON
ReleasedSTP Signal OFF
CHECK:
Measure the voltage between the specified terminals of the E7
and E8 ECM connectors.
OK:
Tester ConnectionBrake PedalSpecified Condition
ST1- (E8-12) - DepressedBelow 1.5 VST1 (E8 12)
E1 (E7-1)
Released7.5 to 14 V
OK Check for intermittent problems (See page
DI-3).
NG
Page 1331 of 3115
A56986
A67404A21228
Wire Harness Side:
Stop Light Switch Connector
ECM Connector S5
ST1-
STP
E8
DI-282
- DIAGNOSTICSENGINE
475 Author: Date:
2004 LAND CRUISER (RM1071U)
5 Check harness and connector between ECM and stop light switch.
PREPARATION:
(a) Disconnect the S5 stop light switch connector.
(b) Disconnect the E8 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
Stop light switch (S5-1) - STP (E8-19)Below 1 W
Stop light switch (S5-4) - ST1- (E8-12)Below 1 W
Stop light switch (S5-1) or
STP (E8-19) - Body ground10 kW or higher
Stop light switch (S5-4) or
ST1- (E8-12) - Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Replace ECM (See page SF-60).
Page 1332 of 3115
- DIAGNOSTICSENGINE
DI-283
476 Author: Date:
2004 LAND CRUISER (RM1071U)
OBD II scan tool (excluding hand-held tester):
1 Check operation of stop light.
CHECK:
Check if the stop lights come on and go off normally when the brake pedal is operated and released.
NG Check and repair stop light circuit.
OK
2 Check STOP fuse.
PREPARATION:
Remove the STOP fuse from the cowl side J/B LH.
CHECK:
Check the continuity of the STOP fuse.
OK:
Continuity
NG Check for short in all harness and components
connected to STOP fuse.
OK
3 Check stop light switch (See page BE-50).
NG Replace stop light switch.
OK
Page 1333 of 3115
A19642
Brake Pedal
DepressedBrake Pedal
Release
STP ON
() ()
ST1-(+)
(+) E8
E7
E1 (-)
DI-284
- DIAGNOSTICSENGINE
477 Author: Date:
2004 LAND CRUISER (RM1071U)
4 Check STP signal.
PREPARATION:
Turn the ignition switch ON.
CHECK:
Measure the voltage between the specified terminals of the E7
and E8 ECM connectors.
OK:
Tester ConnectionBrake Pedal PositionSpecified Condition
STP (E8 19) E1 (E7 1)Depressed7.5 to 14 VSTP (E8-19) - E1 (E7-1)ReleasedBelow 1.5 V
ST1- (E8-12) - DepressedBelow 1.5 VST1 (E8 12)
E1 (E7-1)
Released7.5 to 14 V
OK Check for intermittent problems
(See page DI-3).
NG
Page 1334 of 3115
A56986
A67404A21228
Wire Harness Side:
Stop Light Switch Connector
ECM Connector S5
ST1-
STP
E8
- DIAGNOSTICSENGINE
DI-285
478 Author: Date:
2004 LAND CRUISER (RM1071U)
5 Check harness and connector between ECM and stop light switch.
PREPARATION:
(a) Disconnect the S5 stop light switch connector.
(b) Disconnect the E8 ECM connector.
CHECK:
Measure the resistance between the wire harness side connec-
tors.
OK:
Tester ConnectionSpecified Condition
Stop light switch (S5-1) - STP (E8-19)Below 1 W
Stop light switch (S5-4) - ST1- (E8-12)Below 1 W
Stop light switch (S5-1) or
STP (E8-19) - Body ground10 kW or higher
Stop light switch (S5-4) or
ST1- (E8-12) - Body ground10 kW or higher
NG Repair or replace harness or connector.
OK
Replace ECM (See page SF-60).
Page 1335 of 3115

A20823
Idle engine
RPM
Small Target RPM
Actual idle RPMLarge
Learned value
of the idle speed
controlMaximum
Minimum
Time 0
Time DI-286
- DIAGNOSTICSENGINE
479 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0505 Idle Air Control System
MONITOR DESCRIPTION
The idle speed is controlled by the ETCS (Electronic Throttle Control System).
The ETCS is composed of the throttle motor which operates the throttle valve, and the throttle position sen-
sor, which detects the opening angle of the throttle valve.
The ECM controls the throttle motor to provide the proper throttle valve opening angle to obtain the target
idle speed.
The ECM regulates the idle speed by opening and closing the throttle valve using the ETCS. The ECM con-
cludes that the idle speed control ECM function is malfunctioning if: 1) the actual idle RPM varies more than
the specified amount, or 2) a learned value of the idle speed control remains at the maximum or minimum
five times or more during a drive cycle. The ECM will turn on the MIL and set a DTC.
Example:
If the actual idle RPM varies from the target idle RPM by more than 100 (*1) rpm five times during a drive
cycle, the ECM will turn on the MIL and a DTC is set.
HINT:
*1: RPM threshold varies with engine load.
DTC No.DTC Detecting ConditionTrouble Area
P0505Idle speed continues to vary greatly from target speed
(1 trip detection logic)Electric throttle control system
Air induction system
PCV hose connection
DIC2L-01
Page 1336 of 3115

- DIAGNOSTICSENGINE
DI-287
480 Author: Date:
2004 LAND CRUISER (RM1071U)
MONITOR STRATEGY
Related DTCsP0505Idle air control malfunction
Main sensors/componentsCrankshaft position sensor
Required sensors/componentsRelated sensors/componentsVehicle speed sensor, Engine coolant tempera-
ture sensor
Frequency of operationFunctional check: Once per trip
Range check: Continuous
DurationFunctional check: 10 min.
Range check: 10 sec.
MIL operationFunctional check: 2 driving cycles
Range check: Immediate
Sequence of operationNone
TYPICAL ENABLING CONDITIONS
ItSpecificationItemMinimumMaximum
The monitor will run whenever the follow-
ing DTCs are not presentSee ºList of disable a monitorº (on page DI-3)
Functional check:
Precondition is met when both of the fol-
lowing are metA and B
A. Intake air flow rate learnings is enabled3 sec.-
B. EngineRunning
Range check:
Output signal duty10%90%
Battery voltage10 V-
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Functional check:
Case 1:
All of the following conditions are met:A, B and C
A. Engine RPM - target engine RPM (History that vehicle
had run for 10 km/h (6.2 mph) or more)
Less than -100 rpm or more than 200 rpm
(A/C ON or park/neutral position switch ON)
or
Less than -100 rpm or more than 150 rpm
(A/C OFF and park/neutral position switch OFF)
B. Number of fall judgment5 times or more
C. Intake air control flow rate learning value
Value when fail is judged first + 3.31 L/sec. or more
or
Value when fail is judged first - 3.31 L/sec. or less
Case 2:
Both or the following condition are met:A and B
A. Engine RPM - target engine RPM (History that vehicle
had run for 10 km/h (6.2 mph) or more)
Less than -100 rpm or more than 200 rpm
(A/C ON or park/neutral position switch ON)
or
Less than -100 rpm or more than 150 rpm
(A/C OFF and park/neutral position switch OFF)
B. Intake air control flow rate learning value is for 5 sec.2.48 L/sec. or less or 11 L/sec. or more