2006 INFINITI FX35 speed sensor

EC-12Revision: 2006 December 2006 FX35/FX45 On Board Diagnosis Logic ...................................
11 3 7
DTC Confirmation Procedure .............................. 11 3 7
Wiring Diagram .................................................... 11 3 8
Diagnostic Procedure .......................................... 11 3 9
Component Inspection ......................................... 11 4 1
Removal and Installation ..................................... 11 4 1
DTC P0603 ECM POWER SUPPLY ...................... 114 2
Component Description ....................................... 11 4 2
On Board Diagnosis Logic ................................... 11 4 2
DTC Confirmation Procedure .............................. 11 4 2
Wiring Diagram .................................................... 11 4 3
Diagnostic Procedure .......................................... 11 4 4
DTC P0605 ECM .................................................... 114 6
Component Description ....................................... 11 4 6
On Board Diagnosis Logic ................................... 11 4 6
DTC Confirmation Procedure .............................. 11 4 6
Diagnostic Procedure .......................................... 11 4 7
DTC P0643 SENSOR POWER SUPPLY ............... 114 9
On Board Diagnosis Logic ................................... 11 4 9
DTC Confirmation Procedure .............................. 11 4 9
Wiring Diagram .................................................... 11 5 0
Diagnostic Procedure .......................................... 11 5 2
DTC P0850 PNP SWITCH ..................................... 115 4
Component Description ....................................... 11 5 4
CONSULT-II Reference Value in Data Monitor Mode 11 5 4
On Board Diagnosis Logic ................................... 11 5 4
DTC Confirmation Procedure .............................. 11 5 4
Overall Function Check ....................................... 11 5 5
Wiring Diagram .................................................... 11 5 6
Diagnostic Procedure .......................................... 11 5 7
DTC P1140, P1145 IVT CONTROL POSITION SEN-
SOR ........................................................................ 115 9
Component Description ....................................... 11 5 9
CONSULT-II Reference Value in Data Monitor Mode 11 5 9
On Board Diagnosis Logic ................................... 11 5 9
DTC Confirmation Procedure .............................. 11 5 9
Wiring Diagram .................................................... 11 6 1
Diagnostic Procedure .......................................... 11 6 4
Component Inspection ......................................... 11 6 7
Removal and Installation ..................................... 11 6 7
DTC P1148, P1168 CLOSED LOOP CONTROL ... 116 8
On Board Diagnosis Logic ................................... 11 6 8
DTC P1211 TCS CONTROL UNIT ......................... 116 9
Description ........................................................... 11 6 9
On Board Diagnosis Logic ................................... 11 6 9
DTC Confirmation Procedure .............................. 11 6 9
Diagnostic Procedure .......................................... 11 6 9
DTC P1212 TCS COMMUNICATION LINE ........... 117 0
Description ........................................................... 11 7 0
On Board Diagnosis Logic ................................... 11 7 0
DTC Confirmation Procedure .............................. 11 7 0
Diagnostic Procedure .......................................... 11 7 0
DTC P1217 ENGINE OVER TEMPERATURE ....... 117 1
Description ........................................................... 11 7 1
CONSULT-II Reference Value in Data Monitor Mode 11 7 2
On Board Diagnosis Logic ................................... 11 7 2 Overall Function Check ........................................
11 7 3
Wiring Diagram .................................................... 11 7 5
Diagnostic Procedure ........................................... 11 7 7
Main 13 Causes of Overheating .......................... 11 8 1
Component Inspection ......................................... 11 8 2
DTC P1225 TP SENSOR ....................................... 11 83
Component Description ....................................... 11 8 3
On Board Diagnosis Logic ................................... 11 8 3
DTC Confirmation Procedure ............................... 11 8 3
Diagnostic Procedure ........................................... 11 8 4
Removal and Installation ...................................... 11 8 4
DTC P1226 TP SENSOR ....................................... 11 85
Component Description ....................................... 11 8 5
On Board Diagnosis Logic ................................... 11 8 5
DTC Confirmation Procedure ............................... 11 8 5
Diagnostic Procedure ........................................... 11 8 6
Removal and Installation ...................................... 11 8 6
DTC P1564 ICC STEERING SWITCH ................... 11 87
Component Description ....................................... 11 8 7
CONSULT-II Reference Value in Data Monitor Mode 11 8 7
On Board Diagnosis Logic ................................... 11 8 7
DTC Confirmation Procedure ............................... 11 8 8
Wiring Diagram .................................................... 11 8 9
Diagnostic Procedure ........................................... 11 9 0
Component Inspection ......................................... 11 9 3
DTC P1564 ASCD STEERING SWITCH ............... 11 94
Component Description ....................................... 11 9 4
CONSULT-II Reference Value in Data Monitor Mode 11 9 4
On Board Diagnosis Logic ................................... 11 9 4
DTC Confirmation Procedure ............................... 11 9 5
Wiring Diagram .................................................... 11 9 6
Diagnostic Procedure ........................................... 11 9 7
Component Inspection ......................................... 1200
DTC P1568 ICC FUNCTION .................................. 1201
On Board Diagnosis Logic ................................... 1201
DTC Confirmation Procedure ............................... 1201
Diagnostic Procedure ........................................... 1201
DTC P1572 ICC BRAKE SWITCH ......................... 1202
Component Description ....................................... 1202
CONSULT-II Reference Value in Data Monitor Mode 1202
On Board Diagnosis Logic ................................... 1202
DTC Confirmation Procedure ............................... 1203
Wiring Diagram .................................................... 1204
Diagnostic Procedure ........................................... 1205
Component Inspection ......................................... 1210
DTC P1572 ASCD BRAKE SWITCH ..................... 1211
Component Description ....................................... 1211
CONSULT-II Reference Value in Data Monitor Mode 1211
On Board Diagnosis Logic ................................... 1211
DTC Confirmation Procedure ............................... 1212
Wiring Diagram .................................................... 1213
Diagnostic Procedure ........................................... 1214
Component Inspection ......................................... 1218
DTC P1574 ICC VEHICLE SPEED SENSOR ........ 1219
Component Description ....................................... 1219

EC-13
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Revision: 2006 December 2006 FX35/FX45 On Board Diagnosis Logic ..................................
1219
DTC Confirmation Procedure .............................. 1219
Diagnostic Procedure .......................................... 1220
DTC P1574 ASCD VEHICLE SPEED SENSOR ... 1221
Component Description ....................................... 1221
On Board Diagnosis Logic .................................. 1221
DTC Confirmation Procedure .............................. 1221
Diagnostic Procedure .......................................... 1222
DTC P1715 INPUT SPEED SENSOR (TURBINE
REVOLUTION SENSOR) ...................................... 1223
Description .......................................................... 1223
CONSULT-II Reference Value in Data Monitor Mode 1223
On Board Diagnosis Logic .................................. 1223
Diagnostic Procedure .......................................... 1223
DTC P1800 VIAS CONTROL SOLENOID VALVE 1224 Component Description ....................................... 1224
CONSULT-II Reference Value in Data Monitor Mode 1224
On Board Diagnosis Logic .................................. 1224
DTC Confirmation Procedure .............................. 1224
Wiring Diagram ................................................... 1225
Diagnostic Procedure .......................................... 1226
Component Inspection ........................................ 1227
Removal and Installation ..................................... 1228
DTC P1805 BRAKE SWITCH ............................... 1229
Description .......................................................... 1229
CONSULT-II Reference Value in Data Monitor Mode 1229
On Board Diagnosis Logic .................................. 1229
DTC Confirmation Procedure .............................. 1229
Wiring Diagram ................................................... 1230
Diagnostic Procedure .......................................... 1231
Component Inspection ........................................ 1233
DTC P2100, P2103 THROTTLE CONTROL MOTOR
RELAY ................................................................... 1234
Component Description ....................................... 1234
CONSULT-II Reference Value in Data Monitor Mode 1234
On Board Diagnosis Logic .................................. 1234
DTC Confirmation Procedure .............................. 1234
Wiring Diagram ................................................... 1236
Diagnostic Procedure .......................................... 1237
DTC P2101 ELECTRIC THROTTLE CONTROL
FUNCTION ............................................................. 1240
Description .......................................................... 1240
On Board Diagnosis Logic .................................. 1240
DTC Confirmation Procedure .............................. 1240
Wiring Diagram ................................................... 1241
Diagnostic Procedure .......................................... 1242
Component Inspection ........................................ 1246
Removal and Installation ..................................... 1246
DTC P2118 THROTTLE CONTROL MOTOR ....... 1247
Component Description ....................................... 1247
On Board Diagnosis Logic .................................. 1247
DTC Confirmation Procedure .............................. 1247
Wiring Diagram ................................................... 1248
Diagnostic Procedure .......................................... 1249 Component Inspection .........................................
1250
Removal and Installation ..................................... 1251
DTC P2119 ELECTRIC THROTTLE CONTROL
ACTUATOR ............................................................ 1252
Component Description ....................................... 1252
On Board Diagnosis Logic ................................... 1252
DTC Confirmation Procedure .............................. 1252
Diagnostic Procedure .......................................... 1253
DTC P2122, P2123 APP SENSOR ........................ 1254
Component Description ....................................... 1254
CONSULT-II Reference Value in Data Monitor Mode 1254
On Board Diagnosis Logic ................................... 1254
DTC Confirmation Procedure .............................. 1255
Wiring Diagram .................................................... 1256
Diagnostic Procedure .......................................... 1257
Component Inspection ......................................... 1259
Removal and Installation ..................................... 1260
DTC P2127, P2128 APP SENSOR ........................ 1261
Component Description ....................................... 1261
CONSULT-II Reference Value in Data Monitor Mode 1261
On Board Diagnosis Logic ................................... 1261
DTC Confirmation Procedure .............................. 1262
Wiring Diagram .................................................... 1263
Diagnostic Procedure .......................................... 1264
Component Inspection ......................................... 1267
Removal and Installation ..................................... 1267
DTC P2135 TP SENSOR ....................................... 1268
Component Description ....................................... 1268
CONSULT-II Reference Value in Data Monitor Mode 1268
On Board Diagnosis Logic ................................... 1268
DTC Confirmation Procedure .............................. 1269
Wiring Diagram .................................................... 1270
Diagnostic Procedure .......................................... 1271
Component Inspection ......................................... 1274
Removal and Installation ..................................... 1274
DTC P2138 APP SENSOR .................................... 1275
Component Description ....................................... 1275
CONSULT-II Reference Value in Data Monitor Mode 1275
On Board Diagnosis Logic ................................... 1275
DTC Confirmation Procedure .............................. 1276
Wiring Diagram .................................................... 1277
Diagnostic Procedure .......................................... 1278
Component Inspection ......................................... 1282
Removal and Installation ..................................... 1282
DTC P2A00, P2A03 A/F SENSOR 1 ..................... 1283
Component Description ....................................... 1283
CONSULT-II Reference Value in Data Monitor Mode 1283
On Board Diagnosis Logic ................................... 1283
DTC Confirmation Procedure .............................. 1284
Wiring Diagram .................................................... 1285
Diagnostic Procedure .......................................... 1288
Removal and Installation ..................................... 1294
ASCD BRAKE SWITCH ........................................ 1295
Component Description ....................................... 1295

EC-14Revision: 2006 December 2006 FX35/FX45 CONSULT-II Reference Value in Data Monitor Mode
1295
Wiring Diagram .................................................... 1296
Diagnostic Procedure .......................................... 1297
Component Inspection ......................................... 1301
ASCD INDICATOR ................................................. 1302
Component Description ....................................... 1302
CONSULT-II Reference Value in Data Monitor Mode 1302
Wiring Diagram .................................................... 1303
Diagnostic Procedure .......................................... 1304
ELECTRICAL LOAD SIGNAL ............................... 1305
Description ........................................................... 1305
CONSULT-II Reference Value in Data Monitor Mode 1305
Diagnostic Procedure .......................................... 1305
FUEL INJECTOR ................................................... 1307
Component Description ....................................... 1307
CONSULT-II Reference Value in Data Monitor Mode 1307
Wiring Diagram .................................................... 1308
Diagnostic Procedure .......................................... 1309
Component Inspection ......................................... 1313
Removal and Installation ..................................... 1313
FUEL PUMP ........................................................... 1314
Description ........................................................... 1314
CONSULT-II Reference Value in Data Monitor Mode 1314
Wiring Diagram .................................................... 1315
Diagnostic Procedure .......................................... 1316
Component Inspection ......................................... 1319
Removal and Installation ..................................... 1319
ICC BRAKE SWITCH ............................................. 1320
Component Description ....................................... 1320
CONSULT-II Reference Value in Data Monitor Mode 1320
Wiring Diagram .................................................... 1321
Diagnostic Procedure .......................................... 1322
Component Inspection ......................................... 1327
IGNITION SIGNAL ................................................. 1328
Component Description ....................................... 1328
Wiring Diagram .................................................... 1329 Diagnostic Procedure ...........................................
1334
Component Inspection ......................................... 1339
Removal and Installation ...................................... 1340
REFRIGERANT PRESSURE SENSOR ................. 1341
Component Description ....................................... 1341
Wiring Diagram .................................................... 1342
Diagnostic Procedure ........................................... 1343
Removal and Installation ...................................... 1345
SNOW MODE SWITCH .......................................... 1346
Description ........................................................... 1346
CONSULT-II Reference Value in the Data Monitor
Mode .................................................................... 1346
Wiring Diagram .................................................... 1347
Diagnostic Procedure ........................................... 1348
Component Inspection ......................................... 1350
VARIABLE INDUCTION AIR CONTROL SYSTEM
(VIAS) ..................................................................... 1351
Description ........................................................... 1351
CONSULT-II Reference Value in Data Monitor Mode 1352
Wiring Diagram .................................................... 1353
Diagnostic Procedure ........................................... 1355
Component Inspection ......................................... 1358
Removal and Installation ...................................... 1359
MIL AND DATA LINK CONNECTOR ..................... 1360
Wiring Diagram .................................................... 1360
SERVICE DATA AND SPECIFICATIONS (SDS) ... 1362
Fuel Pressure ....................................................... 1362
Idle Speed and Ignition Timing ............................. 1362
Calculated Load Value ......................................... 1362
Mass Air Flow Sensor .......................................... 1362
Intake Air Temperature Sensor ............................ 1362
Engine Coolant Temperature Sensor ................... 1362
Fuel Tank Temperature Sensor ............................ 1362
Crankshaft Position Sensor (POS) ...................... 1362
Camshaft Position Sensor (PHASE) .................... 1362
A/F Sensor 1 Heater ............................................ 1362
Heated Oxygen sensor 2 Heater ......................... 1363
Throttle Control Motor .......................................... 1363
Fuel Injector ......................................................... 1363
Fuel Pump ............................................................ 1363

INDEX FOR DTC EC-17
[VQ35DE]
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EC
Revision: 2006 December 2006 FX35/FX45P0456 0456 EVAP VERY SML LEAK EC-450
P0460 0460 FUEL LEV SEN SLOSHEC-460
P0461 0461 FUEL LEVEL SENSOREC-462
P0462 0462 FUEL LEVL SEN/CIRCEC-464
P0463 0463 FUEL LEVL SEN/CIRCEC-464
P0500 0500
VEH SPEED SEN/CIRC*5EC-466
P0506 0506 ISC SYSTEM EC-468
P0507 0507 ISC SYSTEMEC-470
P0550 0550 PW ST P SEN/CIRCEC-472
P0603 0603 ECM BACK UP/CIRCUITEC-477
P0605 0605 ECMEC-481
P0643 0643 SENSOR POWER/CIRCEC-484
P0700 0700 TCM AT- 111
P0705 0705 PNP SW/CIRCAT- 11 2
P0710 0710 ATF TEMP SEN/CIRCAT- 1 3 4
P0717 0717 TURBINE SENSOR AT- 11 6
P0720 0720
VEH SPD SEN/CIR AT*5AT- 11 8
P0740 0740 TCC SOLENOID/CIRC AT- 1 2 5
P0744 0744 A/T TCC S/V FNCTNAT- 1 2 7
P0745 0745 L/PRESS SOL/CIRCAT- 1 2 9
P0850 0850 P-N POS SW/CIRCUITEC-489
P1148 1148 CLOSED LOOP-B1EC-494
P1168 1168 CLOSED LOOP-B2EC-494
P1211 1211 TCS C/U FUNCTNEC-495
P1212 1212 TCS/CIRC EC-496
P1217 1217 ENG OVER TEMPEC-497
P1225 1225 CTP LEARNINGEC-510
P1226 1226 CTP LEARNINGEC-512
P1564 1564 ASCD SW EC-514 (Models with ICC),
EC-521
(Models with ASCD)
P1568 1568 ICC COMMAND VALUE*
6EC-528
P1572 1572 ASCD BRAKE SW EC-529 (Models with ICC),
EC-538
(Models with ASCD)
P1574 1574 ASCD VHL SPD SEN EC-546
(Models with ICC),
EC-548
(Models with ASCD)
P1610 - P1615 1610 - 1615 NATS MALFUNCTION EC-550
P1715 1715 IN PULY SPEEDEC-550
P1730 1730 A/T INTERLOCK AT- 1 4 1
P1752 1752 I/C SOLENOID/CIRCAT- 1 4 6
P1754 1754 I/C SOLENOID FNCTNAT- 1 4 8
P1757 1757 FR/B SOLENOID/CIRCAT- 1 5 0
P1759 1759 FR/B SOLENOID FNCTAT- 1 5 2
P1762 1762 D/C SOLENOID/CIRCAT- 1 5 4
DTC*1
Items
(CONSULT-II screen terms) Reference page
CONSULT-II
GST*
2ECM*3

INDEX FOR DTC EC-21
[VQ35DE]
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Revision: 2006 December 2006 FX35/FX45HO2S2 (B1) P0137 0137 EC-270
HO2S2 (B1) P0138 0138EC-281
HO2S2 (B1) P0139 0139EC-294
HO2S2 (B2) P0157 0157EC-270
HO2S2 (B2) P0158 0158EC-281
HO2S2 (B2) P0159 0159EC-294
HO2S2 HTR (B1) P0037 0037EC-173
HO2S2 HTR (B1) P0038 0038EC-173
HO2S2 HTR (B2) P0057 0057EC-173
HO2S2 HTR (B2) P0058 0058EC-173
I/C SOLENOID/CIRC P1752 1752 AT- 1 4 6
I/C SOLENOID FNCTN P1754 1754AT- 1 4 8
IAT SEN/CIRCUIT P0112 0112EC-205
IAT SEN/CIRCUIT P0113 0113EC-205
IAT SENSOR P0127 0127EC-225
ICC COMMAND VALUE*6P1568 1568EC-528
IN PULY SPEED P1715 1715 EC-550
INT/V TIM CONT-B1 P0011 0011EC-161
INT/V TIM CONT-B2 P0021 0021EC-161
INT/V TIM V/CIR-B1 P0075 0075EC-181
INT/V TIM V/CIR-B2 P0081 0081EC-181
ISC SYSTEM P0506 0506EC-468
ISC SYSTEM P0507 0507EC-470
KNOCK SEN/CIRC-B1 P0327 0327EC-356
KNOCK SEN/CIRC-B1 P0328 0328EC-356
L/PRESS SOL/CIRC P0745 0745 AT- 1 2 9
LC/B SOLENOID FNCT P1774 1774AT- 1 6 4
LC/B SOLENOID/CIRC P1772 1772AT- 1 6 2
MAF SEN/CIRCUIT P0101 0101EC-188
MAF SEN/CIRCUIT P0102 0102EC-197
MAF SEN/CIRCUIT P0103 0103EC-197
MULTI CYL MISFIRE P0300 0300EC-346
NATS MALFUNCTION P1610 - P1615 1610 - 1615 EC-53
NO DTC IS DETECTED.
FURTHER TESTING
MAY BE REQUIRED. P0000 0000 —
P-N POS SW/CIRCUIT P0850 0850 EC-489
PNP SW/CIRC P0705 0705 AT- 11 2
PURG VOLUME CONT/V P0443 0443EC-397
PURG VOLUME CONT/V P0444 0444EC-405
PURG VOLUME CONT/V P0445 0445EC-405
PW ST P SEN/CIRC P0550 0550EC-472
SENSOR POWER/CIRC P0643 0643EC-484
Items
(CONSULT-II screen terms) DTC*
1
Reference page
CONSULT-II
GST*
2ECM*3

EC-22
[VQ35DE]
INDEX FOR DTC
Revision: 2006 December 2006 FX35/FX45
*1: 1st trip DTC No. is the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results), this number is controlled by NISSAN.
*4: The troubleshooting for this DTC needs CONSULT-II.
*5: When the fail-safe operations for both self-diagnoses occur, the MIL illuminates.
*6: For models with ICC system. TCM P0700 0700
AT- 111
TCC SOLENOID/CIRC P0740 0740AT-125
TCS C/U FUNCTN P1211 1211EC-495
TCS/CIRC P1212 1212EC-496
THERMSTAT FNCTN P0128 0128EC-228
TP SEN 1/CIRC P0222 0222EC-339
TP SEN 1/CIRC P0223 0223EC-339
TP SEN 2/CIRC P0122 0122EC-215
TP SEN 2/CIRC P0123 0123EC-215
TP SENSOR P2135 2135EC-589
TURBINE SENSOR P0717 0717 AT- 11 6
TW CATALYST SYS-B1 P0420 0420EC-377
TW CATALYST SYS-B2 P0430 0430EC-377
VEH SPD SEN/CIR AT*5P0720 0720AT- 11 8
VEH SPEED SEN/CIRC*5P0500 0500EC-466
VENT CONTROL VALVE P0447 0447 EC-412
VENT CONTROL VALVE P0448 0448EC-419
Items
(CONSULT-II screen terms) DTC*
1
Reference page
CONSULT-II
GST*
2ECM*3

ENGINE CONTROL SYSTEM EC-31
[VQ35DE]
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EC
Revision: 2006 December 2006 FX35/FX45
Multiport Fuel Injection (MFI) SystemNBS003L2
INPUT/OUTPUT SIGNAL CHART
*1: This sensor is not used to control the engine system under normal conditions.
*2: This signal is sent to the ECM through CAN communication line.
*3: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
The amount of fuel injected from the fuel injector is determined by the ECM. The ECM controls the length of
time the valve remains open (injection pulse duration). The amount of fuel injected is a program value in the
ECM memory. The program value is preset by engine operating conditions. These conditions are determined
by input signals (for engine speed and intake air) from both the crankshaft position sensor and the mass air
flow sensor.
VARIOUS FUEL INJECTION INCREASE/DECREASE COMPENSATION
In addition, the amount of fuel injected is compensated to improve engine performance under various operat-
ing conditions as listed below.


During warm-up

When starting the engine

During acceleration

Hot-engine operation

When selector lever is changed from N to D

High-load, high-speed operation


During deceleration

During high engine speed operation
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS) Engine speed*
3
Piston position
Fuel injection
& mixture ratio
control Fuel injector
Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Air fuel ratio (A/F) sensor 1 Density of oxygen in exhaust gas
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Park/neutral position (PNP) switch Gear position
Knock sensor Engine knocking condition
Battery Battery voltage*
3
Power steering pressure sensor Power steering operation
Heated oxygen sensor 2*
1Density of oxygen in exhaust gas
Air conditioner switch Air conditioner operation*
2
Wheel sensorVehicle speed*2

EC-32
[VQ35DE]
ENGINE CONTROL SYSTEM
Revision: 2006 December 2006 FX35/FX45
MIXTURE RATIO FEEDBACK CONTROL (CLOSED LOOP CONTROL)
The mixture ratio feedback system provides the best air-fuel mixture ratio for driveability and emission control.
The three way catalyst 1 can then better reduce CO, HC and NOx emissions. This system uses air fuel ratio
(A/F) sensor 1 in the exhaust manifold to monitor whether the engine operation is rich or lean. The ECM
adjusts the injection pulse width according to the sensor voltage signal. For more information about air fuel
ratio (A/F) sensor 1, refer to EC-240, "
DTC P0131, P0151 A/F SENSOR 1" . This maintains the mixture ratio
within the range of stoichiometric (ideal air-fuel mixture).
This stage is referred to as the closed loop control condition.
Heated oxygen sensor 2 is located downstream of the three way catalyst 1. Even if the switching characteris-
tics of air fuel ratio (A/F) sensor 1 shift, the air-fuel ratio is controlled to stoichiometric by the signal from
heated oxygen sensor 2.
Open Loop Control
The open loop system condition refers to when the ECM detects any of the following conditions. Feedback
control stops in order to maintain stabilized fuel combustion.

Deceleration and acceleration

High-load, high-speed operation

Malfunction of air fuel ratio (A/F) sensor 1 or its circuit

Insufficient activation of air fuel ratio (A/F) sensor 1 at low engine coolant temperature

High engine coolant temperature

During warm-up

After shifting from N to D

When starting the engine
MIXTURE RATIO SELF-LEARNING CONTROL
The mixture ratio feedback control system monitors the mixture ratio signal transmitted from air fuel ratio (A/F)
sensor 1. This feedback signal is then sent to the ECM. The ECM controls the basic mixture ratio as close to
the theoretical mixture ratio as possible. However, the basic mixture ratio is not necessarily controlled as orig-
inally designed. Both manufacturing differences (i.e., mass air flow sensor hot wire) and characteristic
changes during operation (i.e., fuel injector clogging) directly affect mixture ratio.
Accordingly, the difference between the basic and theoretical mixture ratios is monitored in this system. This is
then computed in terms of “injection pulse duration” to automatically compensate for the difference between
the two ratios.
“Fuel trim” refers to the feedback compensation value compared against the basic injection duration. Fuel trim
includes short term fuel trim and long term fuel trim.
“Short term fuel trim” is the short-term fuel compensation used to maintain the mixture ratio at its theoretical
value. The signal from air fuel ratio (A/F) sensor 1 indicates whether the mixture ratio is RICH or LEAN com-
pared to the theoretical value. The signal then triggers a reduction in fuel volume if the mixture ratio is rich, and
an increase in fuel volume if it is lean.
“Long term fuel trim” is overall fuel compensation carried out long-term to compensate for continual deviation
of the short term fuel trim from the central value. Such deviation will occur due to individual engine differences,
wear over time and changes in the usage environment.
PBIB3020E