fuel TOYOTA LAND CRUISER 1986 Factory Service Manual
[x] Cancel search | Manufacturer: TOYOTA, Model Year: 1986, Model line: LAND CRUISER, Model: TOYOTA LAND CRUISER 1986Pages: 3115, PDF Size: 54.88 MB
Page 1157 of 3115
DI-108
- DIAGNOSTICSENGINE
301 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)
There is history that the following condi-
tions A and B were met:20 sec. (Continuously)-
A. Vehicle speed40 km/h (25 mph)-
B. Engine speed900 rpm-
Time after engine start120 sec.-
IdleON
Fuel system statusClosed loop
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
P0130, P0150:
Either of the following conditions A or B is met:3 times or more
A. Front oxygen sensor voltage is 0.55 V or lessFor 18 sec. or more
B. Front oxygen sensor voltage is 0.4 V or moreFor 18 sec. or more
P2195, P2197:
Front heated oxygen sensor voltageConstant 0.55 V or less
P2196, P2198:
Front heated oxygen sensor voltageConstant 0.4 V or more
COMPONENT OPERATING RANGE
ParameterStandard value
In the normal condition, the heated oxygen sensor voltage0 to 1 V
O2S TEST RESULT
Refer to page DI-3 for detailed information.
Front HO2S voltage monitor
If the HO2S voltage is out of the standard value, the ECM interprets this as a malfunction.
TEST IDDescription of TEST DATAConversion FactorUnit
$07Minimum front HO2S voltageN/AV
$08Maximum front HO2S voltageN/AV
WIRING DIAGRAM
Refer to DTC P0031 on page DI-49.
Page 1159 of 3115
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Case 1
Case 2
Case 3
Case 4
Output voltage of heated oxygen
sensor (sensor 1: front sensor)
Injection volume
Output voltage
Output voltage of heated oxygen
sensor (sensor 2: rear sensor)Mainly suspect
trouble area
OK
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
Sensor 1: front sensor
(sensor 1, heater, sensor 1
circuit)
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NGExtremely rich or lean of the
actual air-fuel ratio
(Injector, fuel pressure, gas
leakage in exhaust system,
etc.) OK
OK
OK
Almost no reaction
Almost no reaction
'
Sensor 2: rear sensor
(sensor 2, heater, sensor 2
circuit)
Almost no reaction Almost no reaction
DI-1 10
- DIAGNOSTICSENGINE
303 Author: Date:
2004 LAND CRUISER (RM1071U)
NOTICE:
However, there is a few seconds delay in the sensor 1 (front sensor) output. And there is about 20
seconds delay in the sensor 2 (rear sensor).
The following A/F CONTROL procedure enables the technician to check and graph the voltage output of
the heated oxygen sensors (sensor 1 and 2).
For displaying the graph indication, enter ºACTIVE TEST / A/F CONTROL / USER DATAº then select ºO2S
B1S1 and O2S B1S2º by pressing ºYESº button and push ºENTERº button before pressing ºF4º button.
NOTICE:
If the vehicle is short of fuel, the air-fuel ratio becomes LEAN and heated oxygen sensor DTCs will
be recorded, and the MIL then comes on.
HINT:
If different DTCs related to different systems that have terminal E2 as the ground terminal are output
simultaneously, terminal E2 may be open.
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, it is useful for determin-
ing whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio
was lean or rich, etc. at the time of the malfunction.
A high heated oxygen sensor (sensor 1) voltage (0.5 V or more) could be caused by a rich air fuel mix-
ture. Check for conditions that would cause the engine to run rich.
A low heated oxygen sensor (sensor 1) voltage (0.4 V or less) could be caused by a lean air fuel mix-
ture. Check for conditions that would cause the engine to run lean.
Page 1164 of 3115
A21040
Reference (Bank 1 Sensor 1 System Drawing)
From
BatteryEFI or ECD
No. 1 FuseEFI or ECD
RelayEFI or ECD
No. 2 FuseHeater Oxygen
Sensor
Heater
SensorHT1A
OX1A
E2
MRELECM
- DIAGNOSTICSENGINE
DI-1 15
308 Author: Date:
2004 LAND CRUISER (RM1071U)
NG Repair or replace harness or connector.
OK
6 Check air induction system (See page SF-1).
CHECK:
Check the air induction system for vacuum leaks.
NG Repair or replace
air induction system.
OK
7 Check fuel pressure (See page SF-7).
CHECK:
Check the fuel pressure (high or low pressure).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
Page 1166 of 3115
- DIAGNOSTICSENGINE
DI-1 17
310 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0133 Oxygen Sensor Circuit Slow Response
(Bank 1 Sensor 1)
DTC P0153 Oxygen Sensor Circuit Slow Response
(Bank 2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0031 on page DI-49.
DTC No.DTC Detecting ConditionTrouble Area
P0133
P0153
After engine has been warmed up, if response time that heated
oxygen sensor's output voltage reaches from RICH to LEAN,
or from LEAN to RICH, is 0.6 seconds or more during idling.
(2 trip detection logic)Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Heated oxygen sensor heater
EFI or ECD relay
Ai i d ti tP0153If response time of heated oxygen sensor's output voltage in
one RICH-LEAN cycle is 5.6 seconds or more during idling.
(2 trip detection logic)Air induction system
Fuel pressure
Injector
ECM
HINT:
Bank 1 refers to bank that includes cylinder No. 1.
Bank 2 refers to bank that does not includes cylinder No. 1.
Sensor 1 refers to the sensor closer to the engine assembly.
DIC27-01
Page 1167 of 3115
A20599
0.55
0.40
Oxygen sensor output voltage (V)
Lean to Rich / Rich to Lean time definition
Time Lean to Rich time Rich to Lean time
Rich
Lean Slow slope condition
A20600
Frequency Condition
One Cycle
Rich side frequency
Lean side frequency O2 Sensor Voltage
0.45 V DI-1 18
- DIAGNOSTICSENGINE
311 Author: Date:
2004 LAND CRUISER (RM1071U)
MONITOR DESCRIPTION
The ECM uses the heated oxygen sensor information to regulate the air-fuel ratio close to a stoichiometric
ratio. This maximizes the catalytic converter's ability to purify the exhaust gases. The sensor detects oxygen
levels in the exhaust gas and sends this signal to the ECM.
The inner surface of the sensor element is exposed to outside air. The outer surface of the sensor element
is exposed to exhaust gas. The sensor element is made of platinum coated zirconia and includes an inte-
grated heating element. The heated oxygen sensor has the characteristic whereby its output voltage
changes suddenly in the vicinity of the stoichiometric air-fuel ratio. The heated oxygen sensor generates
waveforms of a voltage between 0 V and 1 V in response to the oxygen concentration in exhaust gas. When
the output voltage of the heated oxygen sensor is 0.55 V or more, the ECM judges that the air-fuel ratio is
RICH. When it is 0.40 V or less, the ECM judges that the air-fuel ratio is LEAN.
The ECM monitors the response feature of the heated oxygen sensor. If the response time of the heated
oxygen sensor output status change from RICH to LEAN or vice versa becomes longer, the ECM interprets
this as a malfunction in the heated oxygen sensor and sets a DTC.
Page 1168 of 3115
- DIAGNOSTICSENGINE
DI-1 19
312 Author: Date:
2004 LAND CRUISER (RM1071U)
MONITOR STRATEGY
RltdDTC
P0133Front heated oxygen sensor response monitor
(Bank 1)
Related DTCs
P0153Front heated oxygen sensor response monitor
(Bank 2)
Main sensors/componentsFront heated oxygen sensor
Required sensors/componentsRelated sensors/componentsCrank position sensor, Vehicle speed sensor,
Mass air flow meter
Frequency of operationOnce per drive cycle
DurationWithin 60 sec.
MIL operation2 driving cycles
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)
Frequency idle condition:
There is history that the following condi-
tions were met for 20 sec.A and B
A. Vehicle speed40 km/h (25 mph)-
B. Engine speed900 rpm-
IdleON
Vehicle speed-5 km/h (3 mph)
Fuel system statusClosed loop
Time after engine start120 sec.-
Engine coolant temperature40°C (104°F)-
Frequency cruise condition:
There is history that the following condi-
tions were met for 20 sec.A and B
A. Vehicle speed40 km/h (25 mph)-
B. Engine speed900 rpm-
Intake air amount3 g/sec.13 g/sec.
Time after engine start120 sec.-
IdleOFF
Fuel system statusClosed loop
Engine speed1,000 rpm3,500 rpm
Engine coolant temperature70°C (158°F)-
Slow slope condition:
Both of the following condition were met
for 20 sec.A and B
A. Vehicle speed40 km/h (25 mph)-
B. Engine speed900 rpm-
Time after engine start120 sec.-
IdleON
Vehicle speed-5 km/h (3 mph)
Page 1169 of 3115
DI-120
- DIAGNOSTICSENGINE
313 Author: Date:
2004 LAND CRUISER (RM1071U) Fuel system status
Closed loop
Engine coolant temperature40°C (104°F)-
TYPICAL MALFUNCTION THRESHOLDS
Detection CriteriaThreshold
Frequency idle condition
Time required by the sensor's output voltage to change in
one RICH-LEAN cycle5.6 sec. or more
Frequency cruise condition
Time required by the sensor's output voltage to change in
one RICH-LEAN cyclea specific time or more
Slow slope condition
Both of the following conditions were metA and B
A. Number of judgment made3 times
B. Following conditions were met(a) or (b)
(a) Average lean to rich response time0.9 sec. or more
(b) Average rich to lean response time0.9 sec. or more
COMPONENT OPERATING RANGE
ParameterStandard value
Voltage output from heated oxygen sensorQuickly fluctuates between 0.4 and 0.55 V
O2S TEST RESULT
Refer to page DI-3 for detailed information.
Front HO2S slow slope monitor
If the HO2S sensor voltage is out of the standard value, the ECM interprets this as a malfunction.
TEST IDDescription of TEST DATAConversion FactorUnit
$03
(Test constant)
Low sensor voltage for response
time calculation
N/AV
$04
(Test constant)
High sensor voltage for response
time calculation
N/AV
If the time required to change is out of the standard value, the ECM interprets this as a malfunction.
TEST IDDescription of TEST DATAConversion FactorUnit
$31Time to change from Lean (0.4
V) to Rich (0.55 V)N/Asec.
$32Time to change from Rich (0.55
V) to Lean (0.4 V)N/Asec.
Front HO2S frequency monitor (idling)
If the $38 is out of the standard value, the ECM interprets this as a malfunction.
TEST IDDescription of TEST DATAConversion FactorUnit
$38
Response time of heated oxygen
sensor's output voltage in one
RICH-LEAN cycle
N/Asec.
Page 1171 of 3115
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Case 1
Case 2
Case 3
Case 4
Output voltage of heated oxygen
sensor (sensor 1: front sensor)
Injection volume
Output voltage
Output voltage of heated oxygen
sensor (sensor 2: rear sensor)Mainly suspect
trouble area
OK
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
Sensor 1: front sensor
(sensor 1, heater, sensor 1
circuit)
+25 %
-12.5 %
More than 0.5 V
Less than 0.4 V
Injection volume
Output voltage
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NG
+25 %
-12.5 %
Injection volume
Output voltage
NGExtremely rich or lean of the
actual air-fuel ratio
(Injector, fuel pressure, gas
leakage in exhaust system,
etc.) OK
OK
OK
Almost no reaction
'
Sensor 2: rear sensor
(sensor 2, heater, sensor 2
circuit)
Almost no reactionAlmost no reaction
Almost no reaction
DI-122
- DIAGNOSTICSENGINE
315 Author: Date:
2004 LAND CRUISER (RM1071U)
The following A/F CONTROL procedure enables the technician to check and graph the voltage output of
the heated oxygen sensors (sensor 1 and 2).
For displaying the graph indication, enter ºACTIVE TEST / A/F CONTROL / USER DATAº then select ºO2S
B1S1 and O2S B1S2º by pressing ºYESº button and push ºENTERº button before pressing ºF4º button.
NOTICE:
If the vehicle is short of fuel, the air-fuel ratio becomes LEAN and DTCs P0133 and/or P0153 will be
recorded, and the MIL then comes on.
If different DTCs related to different systems while terminal E2 as ground terminal are output simulta-
neously, terminal E2 may be open.
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, it is useful for determin-
ing whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio
was lean or rich, etc. at the time of the malfunction.
A high heated oxygen sensor (sensor 1) voltage (0.5 V or more) could be caused by a rich air fuel mix-
ture. Check for conditions that would cause the engine to run rich.
A low heated oxygen sensor (sensor 1) voltage (0.4 V or less) could be caused by a lean air fuel mix-
ture. Check for conditions that would cause the engine to run lean.
Page 1176 of 3115
A21040
Reference (Bank 1 Sensor 1 System Drawing)
From
BatteryEFI or ECD
No. 1 FuseEFI or ECD
RelayEFI or ECD
No. 2 FuseHeater Oxygen
Sensor
Heater
SensorHT1A
OX1A
E2
MRELECM
- DIAGNOSTICSENGINE
DI-127
320 Author: Date:
2004 LAND CRUISER (RM1071U)
NG Repair or replace harness or connector.
OK
6 Check air induction system (See page SF-1).
CHECK:
Check the air induction system for vacuum leaks.
NG Repair or replace air induction system.
OK
7 Check fuel pressure (See page SF-7).
CHECK:
Check the fuel pressure (high or low pressure).
NG Check and repair fuel pump, pressure regulator,
fuel pipe line and filter (See page SF-1).
OK
Page 1178 of 3115
- DIAGNOSTICSENGINE
DI-129
322 Author: Date:
2004 LAND CRUISER (RM1071U)
DTC P0134 Oxygen Sensor Circuit No Activity Detected
(Bank 1 Sensor 1)
DTC P0154 Oxygen Sensor Circuit No Activity Detected
(Bank 2 Sensor 1)
CIRCUIT DESCRIPTION
Refer to DTC P0031 on page DI-49.
DTC No.DTC Detecting ConditionTrouble Area
P0134
P0154
After the engine is warmed up, heated oxygen sensor (bank 1,
sensor 1) output does not indicate RICH (more than 0.45 V)
even once when the following conditions continue for 65 sec.
or more:
(a) Engine speed: 1,400 rpm or more
(b) Vehicle speed: 25 to 81 mph (40 to 130 km/h) or more
(c) Throttle valve does not fully closed
(d) 180 sec. or more after starting engine
(e) Engine coolant temperature more than 40°C (104°F)
Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Heated oxygen sensor heater
EFI or ECD relay
Air induction system
Fuel pressure
PCV hose connection
PCV valve and hose
Injector
Gas leakage on exhaust system
PCV piping
ECM
HINT:
Bank 1 refers to bank that includes cylinder No. 1.
Bank 2 refers to bank that does not includes cylinder No. 1.
Sensor 1 refers to the sensor closer to the engine assembly.
After confirming DTC P0134 and P0154, check the output voltage of the heated oxygen sensor in the
"DIAGNOSIS / ENHANCE OBD II / DATA LIST / ALL" using the OBD II scan tool or the hand-held tester.
If output voltage of the heated oxygen sensor is always less than 0.1 V, heated oxygen sensor circuit
may be open or short.
MONITOR DESCRIPTION
The ECM uses the heated oxygen sensor to optimize the air-fuel mixture in closed-loop fuel control. This
control helps decrease exhaust emissions by providing the catalyst with a nearly stoichiometric mixture.
The sensor detects the oxygen level in the exhaust gas and the ECM uses this data to control the air-fuel
ratio. The sensor output voltage ranges from 0 V to 1 V. If the signal voltage is less than 0.4 V, the air-fuel
ratio is LEAN. If the signal voltage is more than 0.55 V, the air-fuel ratio is RICH. If the conditions for the
closed-loop fuel control are met and after a specified time-period, the sensor's output signal never indicates
RICH, the ECM will conclude that the closed-loop fuel control is malfunctioning. The ECM will illuminate the
MIL and a DTC is set.
DIC28-01