1996 TOYOTA LAND CRUISER Workshop Manual

A00203
CloseOpen Battery
Battery
B1
S1
S2 B2S4
S3
B1
S1 S2 B2S4S3
P24670
P24671
DI−92
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
4 Check operation of the IAC valve .
PREPARATION:
Remove IAC valve (See page SF−51).
CHECK:
(a) Connect the positive (+) leak from the battery to terminals
5 (B1) and 2 (B2), and the negative ( −) lead to terminals
4 (S1), −1 (S2), −6 (S3), −3 (S4) in that order.
(b) Connect the positive (+) lead from the battery to terminals
5 (B1) and 2 (B2), and the negative ( −) lead to terminals
3 (S4), − 6 (S3), −1 (S2), − 4 (S1) in that order.
OK:
(1) The valve moves to close direction.
(2) The valve moves to open direction.
HINT:
The ACTIVE TEST mode of the T OYOTA hand−held tester can
be used to change the step of the IAC valve as desired.
NG Repair or replace IAC valve.
OK
Check and replace ECM (See page IN−28 ).
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−
DIAGNOSTICS ENGINE
DI−93
1996 LAND CRUISER (RM451U)
DTC P0510 Closed Throttle Position Switch Malfunction
CIRCUIT DESCRIPTION
Refer to DTC P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit \
Malfunction) on page DI−35.
DTC No.DTC Detecting ConditionTrouble Area
P0510
The closed throttle position switch does not turn ON or OFF
even once when the vehicle is driven
(2 trip detection logic)Open or short in closed throttle position switch circuit
 Closed throttle position switch
 ECM
HINT:
After confirming DTC P0510 use the TOYOTA hand−held tester to confirm the closed throttle position switch
signal from ”CURRENT DATA”.
Throttle ValveClosed Throttle Position Switch SignalMalfunction
Fully closedOFFOpen circuit
Fully openONShort circuit
WIRING DIAGRAM
Refer to DTC P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit Malfunction) on page DI−35 for WIR-
ING DIAGRAM.
INSPECTION PROCEDURE
HINT:
If DTCs P0110 (Intake Air Temp. Circuit Malfunction), P0115 (Engine Coolant Temp. Circuit Malfunction),
P0120 (Throttle/Pedal Position Sensor/Switch ”A” Circuit Malfunction)\
are output simultaneously, E2 (Sen-
sor Ground) may be open.
TOYOTA hand −held tester
1 Connect the TOYOTA hand −held tester and read CTP switch signal.
PREPARATION:
(a) Remove the fuse cover on the instrument panel.
(b) Connect OBD II scan tool or TOYOTA hand−held tester to the DLC3.
(c) Turn ignition switch ON and OBD II scan tool or TOYOTA hand−held tester main switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
RESULT:
Throttle ValveClosed Throttle Position Switch SignalMalfunction
Fully closedOFFOpen circuit: Go to step 2
Fully openONShort circuit: Go to step 4
DI5PP−02
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BE6653
FI7058A00486
Throttle Position
SensorON
4
3
21
1
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC
IDL
E2 E112V
5V
FI7064
A00487
Throttle Position Sensor
4
3
2
11
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC
IDL
E2 E112V
5V
IDL E2
ON
DI−94
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
2 Check for open in harness or ECM.
PREPARATION:
(a) Disconnect throttle position sensor connector.
(b) Connect sensor wire harness terminals between terminals 1 and 2.
(c) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: ON
OK Confirm good connection at sensor. If OK, replace throttle position sensor.
NG
3 Check for open in harness or ECM.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page SF−65 ).
(b) Connect between terminals IDL and E2 of ECM.
HINT:
Throttle position sensor connector is disconnected.
Before checking, do a visual check and contact pressure check
for connector (See page IN−28).
(c) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: ON
OK Open in harness between ECM and throttle position sensor, repair or replace harness.
NG
Confirm connection at ECM.
If OK, replace ECM (See page IN−28).
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BE6653A00499A00488
Throttle Position Sensor
4
3
2
11
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC IDL1
E2 E112V
5V
ON
BE6653
A00496 A00498
A00489
4
3
2
11
11
9
10
E5
E5
E5 E5
VTA1
ECM
VCC IDL1
E2 12V
5V
ON
Throttle Position
Sensor
E5 Connector
−
DIAGNOSTICS ENGINE
DI−95
1996 LAND CRUISER (RM451U)
4 Check for short in harness or ECM.
PREPARATION:
(a) Disconnect throttle position sensor connector.
(b) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: OFF
OK Confirm good connection at sensor. If OK, replace throttle position sensor.
NG
5 Check for short in harness or ECM.
PREPARATION:
(a) Remove instrument panel speaker No.1 panel (See page SF−65 ).
(b) Disconnect E5 connector of ECM.
HINT:
Throttle position sensor connector is disconnected.
(c) Turn ignition switch ON.
CHECK:
Read CTP switch signal on TOYOTA hand −held tester.
OK:
CTP switch signal: OFF
OK Short in harness between ECM and throttle position sensor, repair or replace harness.
NG
Confirm connection at ECM.
If OK, replace ECM (See page IN−28).
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A00492
43
2
11
11
9
10
E5
E5
E5 E5
VTA
ECM
VCC
IDL
E2E1 12V
5V
ON
Throttle Position Sensor
DI−96
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
OBD II scan tool (excluding TOYOTA hand −held tester)
1 Check for open and short in harness or ECM.
PREPARATION:
(a) Disconnect throttle position sensor connector.
(b) Turn ignition switch ON.
CHECK:
Measure voltage between terminals 1 and 2 of throttle position
sensor connector.
OK:
Voltage: 9 − 14 V
OK Confirm good connection at sensor. If OK, replace throttle position sensor.
NG
2 Check for open and short in harness and connector between throttle posit\
ion sensor and ECM (See page IN−28).
NG Open or short in harness between ECM and
throttle position sensor.
OK
Confirm connection at ECM.
If OK, replace ECM (See page IN−28).
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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
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A00183
ON(+)
(−)IGF
BE6653
P24673
DI−98
−
DIAGNOSTICS ENGINE
1996 LAND CRUISER (RM451U)
INSPECTION PROCEDURE
1 Check for spark (See page IG−1).
NG Go to step 4.
OK
2 Check for open and short in harness and connector in IGF signal circuit \
between ECM and igniter (See page IN−28).
NG Repair or replace harness or connector.
OK
3 Disconnect igniter connector and check voltage between terminal IGF of E\
CM connector and body ground.
PREPARATION:
(a) Disconnect igniter connector.
(b) Remove instrument panel speaker No.1 panel (See page
SF−65 ).
(c) Turn ignition switch ON.
CHECK:
Measure voltage between terminal IGF of ECM connector and
body ground.
OK:
Voltage: 4.5 − 5.5 V
OK Replace igniter.
NG
Check and replace ECM (See page IN−28 ).
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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
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