TOYOTA LAND CRUISER 1998 Factory Repair Manual

A21043
Starter Relay EFI Relay
Circuit Opening
Relay
Fuel Pump RelayMREL
FPRTr2
Tr1 EFI
IGNECM
FC
NE Fuel Pump
Battery
StarterFuel Pump Resistor
AM2Ignition Switch
STA
Crankshaft Position
Sensor (NE Signal) DI-162
- DIAGNOSTICSENGINE
355 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P0230 Fuel Pump Primary Circuit
CIRCUIT DESCRIPTION
In the diagram below, when the engine is cranked, current flows from terminal STAR of the ECM to the starter
relay coil and also current flows to terminal STA of the ECM (STA signal).
When the STA signal and NE signal are input to the ECM, the Tr1 is turned ON, current flows to the coil of
the circuit opening relay, the relay switches on, power is supplied to the fuel pump, and the fuel pump oper-
ates.
While the NE signal is generated (engine running), the ECM keeps the Tr1 ON (circuit opening relay ON)
and the fuel pump also keeps operating.
The fuel pump speed is controlled at two levels (high speed or low speed) by the condition of the engine
(starting, light load, heavy load). When the engine starts (STA ON), the Tr2 in the ECM is OFF, so the fuel
pump relay closes and battery positive voltage is applied directly to the fuel pump. The fuel pump operates
at high speed.
After the engine starts during idling or light loads, since the Tr2 goes ON, power is supplied to the fuel pump
via the fuel pump resistor. The fuel pump operates at low speed.
DIC2B-01

- DIAGNOSTICSENGINE
DI-163
356 Author
: Date
:
2004 LAND CRUISER (RM1071U)DTC No.
DTC Detecting ConditionTrouble Area
P0230Open or short in fuel pump relay circuit

Open or short in fuel pump relay circuit

Fuel pump relay

Circuit opening relay

Fuel pump

ECM

A19965A20085
ECM
FPR
FC
MREL Engine Room R/B
Engine Room J/B
Cowl Side J/B RH Cowl Side J/B LH
I18
Ignition SW
Cowl Side J/B LHJ/B No. 5
J4
J/C
MAINJ/B No. 6
F15
FL Block Fuel Pump
Relay
C/OPN Relay
EFI or ECD Relay
EFI or ECD No. 1
AM2
IGN
Battery 1
1
1
1
1
111 1 1 1 1 1
1 2 35 4
3
125
1
2 3
4 R-L
R-L
R-LB
BB
IA29
BB1
2
G-W6D
6C710
G-W
B-Y
B-Y
W-BG-W
B-W
B-WF12
Fuel
Pump
1
4
2 16
13
155C 5D
5C 5D
5C 5D B-R
B-Y
B-W
B-YM4
5 B
W-B33
E5
10
8 E9
E9
BB1 8
W-B 1A
1B
1B
1B 1C1 9 11 44 43
422
3E3B
AA B-R
B-RB-R
6 7
2K 2A 2E W-R W-R
B-G
W-B
33
IF EAB-W
B-W
F14 Fuel Pump
Resistor
L-B
4110
2 IG2 AM2If113
G-WG-W 12
DI-164
- DIAGNOSTICSENGINE
357 Author
: Date
:
2004 LAND CRUISER (RM1071U)
WIRING DIAGRAM
HINT:
This diagnostic chart is based on premise that engine is started. If the engine is not started, proceed to prob-
lem symptoms table on DI-48.

A19522A19630
E5E7E1
FPR
ECM Connector
A21024
- DIAGNOSTICSENGINE
DI-165
358 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.
1 Check voltage between terminal FPR and E1 of ECM.
CHECK:
Measure the voltage between terminals of E5 and E7 ECM con-
nectors.
OK:
Tester ConnectionConditionSpecified Condition
FPR (E5-33) - E1 (E7-1)STA signal ON9 to 14 V
FPR (E5-33) - E1 (E7-1)STA signal OFF0 to 3 V
OK Replace ECM (See page SF-60).
NG
2 Check fuel pump relay.
PREPARATION:
Remove the fuel pump relay from the engine room R/B.
CHECK:
Inspect the fuel pump relay.
OK:
Tester ConnectionSpecified Condition
1 - 2Continuity
3 - 4Continuity
3 - 5 No continuity
3 - 5Continuity
(Apply battery voltage terminal 1 and 2)
NG Replace fuel pump relay.
OK

A21342
Engine Room J/B:
Fuel Pump
Relay
A21023
E5
ECM Connector FPR
DI-166
- DIAGNOSTICSENGINE
359 Author
: Date
:
2004 LAND CRUISER (RM1071U)
3 Check for open and short in harness and connector between fuel pump relay
and ECM.
PREPARATION:
(a) Remove the fuel pump relay from the engine room J/B.
(b) Disconnect the E5 ECM connector.
CHECK:
Measure the resistance between wire harness side connectors.
OK:
Tester ConnectionSpecified Condition
Engine Room J/B (Fuel pump relay ter-
minal 1) - FPR (E5-33)Below 1 W
Engine Room J/B (Fuel pump relay ter-
minal 1) or FPR (E5-33) -
Body ground
10 kW or higher
NG Repair or replace harness or connector.
OK
Replace ECM (See page SF-60).

- DIAGNOSTICSENGINE
DI-167
360 Author
: Date
:
2004 LAND CRUISER (RM1071U)
DTC P0300 Random/Multiple Cylinder Misfire Detected
DTC P0301 Cylinder 1 Misfire Detected
DTC P0302 Cylinder 2 Misfire Detected
DTC P0303 Cylinder 3 Misfire Detected
DTC P0304 Cylinder 4 Misfire Detected
DTC P0305 Cylinder 5 Misfire Detected
DTC P0306 Cylinder 6 Misfire Detected
DTC P0307 Cylinder 7 Misfire Detected
DTC P0308 Cylinder 8 Misfire Detected
CIRCUIT DESCRIPTION
When a misfire occurs in the engine, hydrocarbons (HC) enter the exhaust in high concentrations. If this HC
concentration is high enough, there could be an increase in exhaust emissions levels. High concentrations
of HC can also cause to temperature of the catalyst to increase, possibly damaging the catalyst. To prevent
this increase in emissions and limit the possibility of thermal damage, the ECM monitors the misfire rate.
When the temperature of the catalyst reaches a point of thermal degradation, the ECM will blink the MIL.
For monitoring misfire, the ECM uses both the camshaft position sensor and the crankshaft position sensor.
The camshaft position sensor is used to identify misfiring cylinders and the crankshaft position sensor is used
to measure variations in the crankshaft rotation speed. The misfire counter increments when crankshaft rota-
tion speed variations exceed threshold values.
If the misfiring rate exceeds the threshold value and could cause emissions deterioration, the ECM illumi-
nates the MIL.
DIC2C-01

A20646
20V
/Division Injector Signal Waveform
20V
/Division
GND
100 msec./Division (Idling)(Magnification)
GND
1 msec./Division (Idling)
Injection duration
DI-168
- DIAGNOSTICSENGINE
361 Author
: Date
:
2004 LAND CRUISER (RM1071U)DTC No.
DTC Detecting ConditionTrouble Area
P0300Misfiring of random cylinders is detected

Open or short in engine wire

Connector connection

Vacuum hose connection
P0301
P0302
P0303
P0304
P0305
P0306
P0307
P0308
Misfiring of each cylinder is detected

Vacuum hose connection

Ignition system

Injector

Fuel pressure

Mass air flow meter

Engine coolant temperature sensor

Compression pressure

Valve clearance

Valve timing

PCV piping

ECM
HINT:
When several codes for a misfiring cylinder are recorded repeatedly but no random misfire code is recorded,
it indicates that the misfires have been detected and recorded at different times.
Reference: Inspection using the oscilloscope.
With the engine idling, check the waveform between terminals #1 to #8 and E01 of the ECM connectors.
HINT:
The correct waveform is as shown.

Crankshaft position sensor
(36-2 teeth or 12 teeth) Camshaft position sensor
ECM
A20490
- DIAGNOSTICSENGINE
DI-169
362 Author
: Date
:
2004 LAND CRUISER (RM1071U)
MONITOR DESCRIPTION
The ECM illuminates the MIL (2 trip detection logic) if:
The ECM will illuminate the MIL when the percent misfire exceeds the specified limit per 1,000 engine revolu-
tions. One occurrence of excessive misfire during engine start will set the MIL. Four occurrences are required
to set the MIL 1,000 revolutions after engine start.
The ECM blinks the MIL (MIL blinks immediately) if:

Within 200 engine revolutions at a high rpm, the threshold for ºpercent of misfire causing catalyst dam-
ageº is reached 1 time.

Within 200 engine revolutions at a normal rpm, the threshold for ºpercent of misfire causing catalyst
damageº is reached 3 time.
MONITOR STRATEGY
P0300Random/Multiple cylinder misfire detected
P0301Cylinder 1 misfire detected
P0302Cylinder 2 misfire detected
P0303Cylinder 3 misfire detected
Related DTCsP0304Cylinder 4 misfire detectedRelated DTCs
P0305Cylinder 5 misfire detected
P0306Cylinder 6 misfire detected
P0307Cylinder 7 misfire detected
P0308Cylinder 8 misfire detected
Rid / t
Main sensors/componentsCamshaft position sensor, Crankshaft position
sensor
Required sensors/components
Related sensors/componentsEngine coolant temperature sensor, Intake air
temperature sensor, Throttle position sensor
Frequency of operationContinuous
DurationEvery 1,000 revolutions (soon after engine is started: 1 time, other 4 times) (emission related misfire)
Every 200 revolutions (1 or 3 times) (catalyst deteriorating misfire)
MIL operation2 driving cycles MIL ON
Immediate MIL blinking (Catalyst deteriorating misfire)
Sequence of operationNone

DI-170
- DIAGNOSTICSENGINE
363 Author
: Date
:
2004 LAND CRUISER (RM1071U)
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)
Battery voltage8 V-
VVTNormal operation (i. e. not under scan-tool control)
Engine speed fluctuationEngine speed should not have changed rapidly
Engine speed (Two full revolutions (2 rev.)
after engine has started)400 rpm5,300 rpm
All of the following conditions are met:A, B and C
A. Engine coolant temperature-10C (14F)-
B. Either of the following conditions is met:(a) or (b)
(a) Intake air temperature-10C (14F)-
(b) Engine coolant temperature75C (167F)-
C. Either of the following conditions is
met:(a) or (b)
(a) Engine coolant temperature at engine
started-7C (19F)-
(b) Engine coolant temperature20C (68F)-
Intake air amount per revolution (varies
with engine speed)0.4 g/rev.-
Throttle position learningCompleted
Rapid throttle opening or closing operation has not occurred
Throttle position-Changing value of throttle position
Less than 0.5 per 0.008 sec.
Rough road counter-14 times/1,000 revolutions
(Not running on rough road)
For paired cylinder misfire (6 or 8 cylinders):
When ECT is between -10C (14F) and
75C (167F), the following conditions are
met:
A and B
A. Engine speed-3,000 rpm
B. Intake air amount per revolution at
1,800 rpm (varies with engine speed)0.7 g/sec.-
When ECT is over 75C (167F), the fol-
lowing conditions are met:A or (B and C)
A. NE signal plate tooth width learning was not completed
B. Engine speed-3,000 rpm
C. Intake air amount per revolution at
1,800 rpm (varies with engine speed)0.7 g/sec.-

A19966
Battery I18
Ignition SW
#8#6 #4 #2
#7 #5ECM
#3 #1
7
5 2 1
4
3 3
1C1 F15
FL BlockEngine Room J/B
1B 6Cowl Side J/B LH
6
E7
E7 E6E5
Y
W G R
IG2
AM2E5 E5 E5 E5
5 I9
Injector No. 1
I16
Injector No. 8 I15
Injector No. 7 I14
Injector No. 6 I13
Injector No. 5 I12
Injector No. 4 I11
Injector No. 3 I10
Injector No. 2
AAJ4
J/C
Ib2 IN2712
AM22E 41
2A 10
9
2B-G
MAIN
B-W R-LL B 12
12 12 12
12 12 12 12
W-R W-R W-R B-R B-R B-R B-RB-R
B-R B-RB-R B-R B-R B-R B-R
B-RB-RB-R B-R B-R
- DIAGNOSTICSENGINE
DI-171
364 Author
: Date
:
2004 LAND CRUISER (RM1071U)
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Emission related misfire rate:
1. During the first 1,000 revolutions after engine start
(MIL is set when misfire is detected 1 time)
2. After the first 1,000 revolutions have occurred
(MIL is set when misfire is detected 4 times)
3 %/1,000 revolutions
Catalyst damage misfire count:
1. Low engine rpm area (ex. less than 3,000 rpm):
200 revolutions (MIL is set when misfire is detected 3
times)
2. High engine rpm area: Every 200 revolutions
96 count/200 revolutions
(Threshold varies with engine speed and intake air amount per revolution)
WIRING DIAGRAM
Refer to DTC P0351 on page DI-202 for the wiring diagram of the ignition system.