1996 TOYOTA LAND CRUISER Cruise control

P22475
BatteryFusible
Link
FL AM2
F7W−R
EA2
W−R
B−R B−R
EA2
B−R
B−W B−W
W−B
Distributor
Ignition
Coil 4
12
EA2
IH1
W−B
8 1
2
Noise
Filter 45
B 3
Igniter Tr2
2
1
IH2 IH2
B−G
B−G
B−Y B−YE4
E4 IGT
IGF Tr15V
ECM
1 3 11
6
IG Switch
1
EC
17 23
14 13
−
DIAGNOSTICS ENGINE
DI−97
1996 LAND CRUISER (RM451U)
DTC P1300 Igniter Circuit Malfunction
CIRCUIT DESCRIPTION
The ECM determines the ignition timing, turns on Tr1 at a predetermined angle ( °CA) before the desired
ignition timing and outputs and ignition signal (IGT) ”1” to the\
igniter.
Since the width of the IGT signal is constant, the dwell angle control circuit in \
the igniter determines the time
the control circuit starts primary current flow to the ignition coil based \
on the engine rpm and ignition timing
one revolution ago, that is, the time the Tr2 turns on.
When it reaches the ignition timing, the ECM turns Tr1 off and outputs the IGT signal ”O”.
This turns Tr2 off, interrupting the primary current flow and generating a high voltage i\
n the secondary coil
which causes the spark plug to spark. Also, by the counter electromotive forc\
e generated when the primary
current is interrupted, the igniter sends an ignition confirmation signal (IGF)\
to the ECM. The ECM stops fuel
injection as a fail safe function when the IGF signal is not input to the ECM.
DTC No.DTC Detecting ConditionTrouble Area
P1300No IGF signal to ECM for 6 consecutive IGT signals during
engine running Open or short in IGF or IGT circuit from igniter to ECM
 Igniter
 ECM
WIRING DIAGRAM
DI5PQ−02
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

A00184
STARTIGT
(+)(−)
BE6653
P24674
FI6605
IGT signal waveform
5 m sec/Division (Idling)
IGT
IGF
2 V/Div.
0V 0V
−
DIAGNOSTICS ENGINE
DI−99
1996 LAND CRUISER (RM451U)
4 Check for open and short in harness and connector in IGT signal circuit betwe\
en
ECM and igniter (See page IN−28).
NG Repair or replace harness or connector.
OK
5 Check voltage between terminals IGT of ECM connector and body ground.
PREPARATION:
Remove instrument panel speaker No.1 panel (See page
SF−65 ).
CHECK:
Measure voltage between terminal IGT of ECM connector and
body ground when engine is cranked.
OK:
Voltage: More than 0.1 V and less than 4.5 V
Reference: INSPECTION USING OSCILLOSCOPE
During cranking or idling, check waveforms between terminals
IGT and E1 of engine control module.
HINT:
The correct regulator waveforms are as shown.
NG Check and replace ECM (See page IN−28 ).
NG
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

A15825
−
DIAGNOSTICS ENGINE
DI−103
1996 LAND CRUISER (RM451U)
DTC P1500 Starter Signal Circuit Malfunction
CIRCUIT DESCRIPTION
When the engine is cranked, the intake air flow is slow, so fuel vaporization is poor. A rich mixture is therefore
necessary in order to achieve good startability. While the engine is being cranked, the battery positive volt-
age is applied to terminal STA of the ECM. The starter signal is mainly used to increase the fuel inj\
ection
volume for the starting injection control and after −start injection control.
WIRING DIAGRAM
DI968−01
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

P22477
BatteryFusible Link
E8
1 W
2 2
EFI
R/B No.2
R−YR−Y
EA2E7ECM
BATT
2
FL MAIN
2
−
DIAGNOSTICS ENGINE
DI−105
1996 LAND CRUISER (RM451U)
DTC P1600 ECM BATT Malfunction
CIRCUIT DESCRIPTION
Battery positive voltage is supplied to terminal BATT of the ECM even when the ignition switch is OFF for
use by the DTC memory and air −fuel ratio adaptive control value memory, etc.
DTC No.DTC Detecting ConditionTrouble Area
P1600Open in back up power source circuitOpen in back up power source circuit
 ECM
HINT:
If DTC P1600 appear, the ECM does not store another DTC.
WIRING DIAGRAM
DI5PT−02
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

−
DIAGNOSTICS ENGINE
DI−107
1996 LAND CRUISER (RM451U)
DTC P1605 Knock Control CPU Malfunction
CIRCUIT DESCRIPTION
Refer to DTC P0325, P0330 (Knock Sensor 1, 2 Circuit Malfunction) on page DI−59.
DTC No.DTC Detecting ConditionTrouble Area
P1605Engine control computer malfunction (for knock control)ECM
WIRING DIAGRAM
Refer to P0325, P0330 (Knock Sensor 1, 2 Circuit Malfunction) on page DI−59.
INSPECTION PROCEDURE
1 Are there any other codes (besides DTC P1605) being output?
YES Go to relevant DTC chart.
NO
Check and replace ECM (See page IN−28 ).
DI5PU−02
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

P22478
Battery
FL AM1
Fusible Link
1F6
B−L
2
2 2
2
3
4
AM1
R/B No.2
Junction
Connector (J4)
Y Y
IG Switch
4 2
1 B−W
B−YFuse Block
GAUGE
Y
B
B 6IH14
B−W Park/Neutral
Position Switch
3
2 G−R G−W
O
O
IH2
To A/T Indicator Light
(Combination Meter)
Starter
1
S1 E7
E7
E7
17
16
22 NSW
E1B+
E1 E1
L
2 ECM
W
EA26
B
B
B−R
65 3
2IH1
21
B−W
IH2
DI−108
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
DTC P1780 Park/Neutral Position Switch Malfunction
CIRCUIT DESCRIPTION
The park/neutral position switch goes on when the shift lever is in the N o\
r P shift position. When it goes on
terminal NSW of the ECM is grounded to body ground via the starter relay, thus the terminal NSW voltage
becomes 0 V. When the shift lever is in the D, 2, L or R position, the park/neutral\
position switch goes off,
so the voltage of ECM, terminal NSW becomes battery voltage, the voltage of the ECM internal power
source. If the shift lever is moved from the N position to the D position, this signal is used for air\
−fuel ratio
correction and for idle speed control (estimated control), etc.
DTC No.DTC Detecting ConditionTrouble Area
P1780
2 or more switches are ON simultaneously for ”N”, ”2” and ”\
L”
position (2 trip detection logic)
 Short in park/neutral position switch circuit
 Park/neutral position switch
 ECMWhen driving under conditions (a) and (b) for 30 sec. or more
the park/neutral position switch is ON (N position):
(2 trip detection logic)
(a) Vehicle speed: 70 km/h (44 mph) or more
(b) Engine speed: 1,500 − 2,500 rpm
HINT:
After confirming DTC P1780 use the T OYOTA hand−held tester to confirm the PNP switch signal from ”CUR-
RENT DATA”.
WIRING DIAGRAM
DI5PV−02
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

P22480
BatteryStarter
FL MAIN
FL AM2EFI
EFI Main Relay
IG Switch IG
ST
Park/Neutral
Position SwitchCircuit Opening
Relay
Fuel Pump Relay
Fuel Pump
From Crankshaft Position
Sensor Fuel Pump
Resistor
(STA Signal)
(NE Signal) MRLY
FC
STA
NE
Tr1
Tr2
ECM
IGN FPR
−
DIAGNOSTICS ENGINE
DI−11 5
1996 LAND CRUISER (RM451U)
Fuel Pump Control Circuit
CIRCUIT DESCRIPTION
In the diagram below, when the engine is cranked, current flows form terminal ST of the igni\
tion switch to
terminal STA of ECM (STA signal).
When the STA signal and NE signal are input to the ECM, Tr1 is turned ON, current flows to coil of the circuit
opening relay, the relay switches on, power is supplied to the fuel pump and the fuel\
pump operates.
While the NE signal is generated (engine running), the ECM keeps Tr1 ON (circuit opening relay ON) and
the fuel pump also keeps operating.
The fuel pump speed is controlled at 2 levels (high speed or low speed) b\
y the condition of the engine (start-
ing, light load, heavy load). When the engine starts (STA ON), Tr2 in the ECM is OFF, so battery voltage is
applied directry to the fuel pump. Fuel pump operates at high speed.
After the engine starts, during idling or light loads, since Tr2 goes ON, power is supplied to the fuel pump
via the fuel pump resistor.
Fuel pump operates at low speed.
DI5PY−02
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010

P22216
Pressure RegulatorVSV
ECM
To Fuel Tank
(Return)
From Delivery Pipe Intake
Manifold
P22482
BRFrom BatteryR/B No.2EB
2
2
2
2
EFI Main
22Y−R
Y−R
EB11
REA27R
R−Y
EZ1
VSV for Fuel21
EZ1
Relay
EFI
12 4
3
1B B3
L−R
Pressure Control E7
E4 3
21 FPU
MRLY
ECM
B+
E01
−
DIAGNOSTICS ENGINE
DI−125
1996 LAND CRUISER (RM451U)
Fuel Pressure Control Circuit
CIRCUIT DESCRIPTION
The ECM turns on a VSV (V acuum Switching Valve) to draw the
air into the diaphragm chamber of the pressure regulator if it de-
tects that the temperature of the engine coolant is too high dur-
ing engine starting.
The air drawn into the chamber increases the fuel pressure to
prevent fuel vapor lock at high engine temperature in order to
help the engine start when it is warm.
Fuel pressure control ends approx. 120 sec. after the engine is
started.
WIRING DIAGRAM
DI5PZ−02
Brought to you by BirfMark
Brought to you by BirfMark
Version 1.11 - 03/16/2010