EC-1
ENGINE CONTROL SYSTEM
B ENGINE
CONTENTS
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SECTION EC
A
EC
ENGINE CONTROL SYSTEM
QR
INDEX FOR DTC ...................................................... 10
DTC No. Index ....................................................... 10
Alphabetical Index .................................................. 12
PRECAUTIONS ........................................................ 14
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ................................................................ 14
On Board Diagnostic (OBD) System of Engine ...... 14
Precaution .............................................................. 14
PREPARATION ......................................................... 18
Special Service Tools ............................................. 18
Commercial Service Tools ...................................... 19
ENGINE CONTROL SYSTEM .................................. 20
System Diagram ..................................................... 20
Multiport Fuel Injection (MFI) System .................... 21
Electronic Ignition (EI) System ............................... 23
Fuel Cut Control (At No Load and High Engine
Speed) .................................................................... 24
AIR CONDITIONING CUT CONTROL ..................... 25
Input/Output Signal Chart ....................................... 25
CAN COMMUNICATION .......................................... 26
System Description ................................................ 26
EVAPORATIVE EMISSION SYSTEM ....................... 27
Description ............................................................. 27
Component Inspection ........................................... 29
POSITIVE CRANKCASE VENTILATION ................. 30
Description ............................................................. 30
Component Inspection ........................................... 30
NATS (NISSAN ANTI-THEFT SYSTEM) .................. 32
Description ............................................................. 32
ON BOARD DIAGNOSTIC (OBD) SYSTEM ............ 33
Introduction ............................................................ 33
Two Trip Detection Logic ........................................ 33
Emission-related Diagnostic Information ................ 33
Malfunction Indicator (MI) ....................................... 36
BASIC SERVICE PROCEDURE .............................. 40
Basic Inspection ..................................................... 40
Idle Speed and Ignition Timing Check .................... 45
Procedure After Replacing ECM ............................ 47Accelerator Pedal Released Position Learning ...... 47
Throttle Valve Closed Position Learning ................. 47
Idle Air Volume Learning ........................................ 47
Fuel Pressure Check .............................................. 49
TROUBLE DIAGNOSIS ............................................ 52
Trouble Diagnosis Introduction ............................... 52
DTC Inspection Priority Chart ................................. 58
Fail-Safe Chart ....................................................... 59
Symptom Matrix Chart ............................................ 60
Engine Control Component Parts Location ............ 64
Vacuum Hose Drawing ........................................... 69
Circuit Diagram ....................................................... 70
ECM Harness Connector Terminal Layout ............. 72
ECM Terminals and Reference Value ..................... 72
CONSULT-II Function (ENGINE) ............................ 80
CONSULT-II Reference Value in Data Monitor Mode
... 90
Major Sensor Reference Graph in Data Monitor
Mode ....................................................................... 93
TROUBLE DIAGNOSIS - SPECIFICATION VALUE ... 95
Description .............................................................. 95
Testing Condition .................................................... 95
Inspection Procedure .............................................. 95
Diagnostic Procedure ............................................. 96
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
DENT .......................................................................105
Description ............................................................105
Diagnostic Procedure ...........................................105
POWER SUPPLY AND GROUND CIRCUIT ...........106
Wiring Diagram .....................................................106
Diagnostic Procedure ...........................................107
Ground Inspection .................................................111
DTC U1000, U1001 CAN COMMUNICATION LINE .113
Description ............................................................113
On Board Diagnosis Logic ....................................113
DTC Confirmation Procedure ...............................113
Wiring Diagram .....................................................114
Diagnostic Procedure ...........................................115
DTC P0011 IVT CONTROL .....................................116
Description ............................................................116
EC-4 DTC P2138 APP SENSOR .....................................272
Component Description ........................................272
CONSULT-II Reference Value in Data Monitor Mode
.272
On Board Diagnosis Logic ....................................272
DTC Confirmation Procedure ...............................273
Wiring Diagram .....................................................274
Diagnostic Procedure ...........................................275
Component Inspection ..........................................279
Removal and Installation ......................................279
ELECTRICAL LOAD SIGNAL ................................280
Description ............................................................280
CONSULT-II Reference Value in Data Monitor Mode
.280
Diagnostic Procedure ...........................................280
EVAP CANISTER PURGE VOLUME CONTROL
SOLENOID VALVE .................................................282
Description ............................................................282
CONSULT-II Reference Value in Data Monitor Mode
.282
Wiring Diagram .....................................................283
Diagnostic Procedure ...........................................285
Component Inspection ..........................................288
Removal and Installation ......................................288
FUEL INJECTOR ....................................................289
Component Description ........................................289
CONSULT-II Reference Value in Data Monitor Mode
.289
Wiring Diagram .....................................................290
Diagnostic Procedure ...........................................291
Component Inspection ..........................................293
Removal and Installation ......................................294
FUEL PUMP ............................................................295
Description ............................................................295
CONSULT-II Reference Value in Data Monitor Mode
.295
Wiring Diagram .....................................................296
Diagnostic Procedure ...........................................297
Component Inspection ..........................................300
Removal and Installation ......................................300
HO2S1 .....................................................................301
Component Description ........................................301
CONSULT-II Reference Value in Data Monitor Mode
.301
Wiring Diagram .....................................................302
Diagnostic Procedure ...........................................304
Component Inspection ..........................................305
Removal and Installation ......................................307
HO2S1 HEATER .....................................................308
Description ............................................................308
CONSULT-II Reference Value in Data Monitor Mode
.308
Wiring Diagram .....................................................309
Diagnostic Procedure ...........................................310
Component Inspection ..........................................312
Removal and Installation ......................................312
HO2S2 .....................................................................313
Component Description ........................................313CONSULT-II Reference Value in Data Monitor Mode
.313
Wiring Diagram .....................................................314
Diagnostic Procedure ............................................315
Component Inspection ..........................................317
Removal and Installation .......................................318
HO2S2 HEATER ......................................................319
Description ............................................................319
CONSULT-II Reference Value in Data Monitor Mode
.319
Wiring Diagram .....................................................320
Diagnostic Procedure ............................................321
Component Inspection ..........................................323
Removal and Installation .......................................323
IAT SENSOR ...........................................................324
Component Description ........................................324
Wiring Diagram .....................................................325
Diagnostic Procedure ............................................326
Component Inspection ..........................................328
Removal and Installation .......................................328
IGNITION SIGNAL ..................................................329
Component Description ........................................329
Wiring Diagram .....................................................330
Diagnostic Procedure ............................................333
Component Inspection ..........................................337
Removal and Installation .......................................338
REFRIGERANT PRESSURE SENSOR ..................339
Component Description ........................................339
Wiring Diagram .....................................................340
Diagnostic Procedure ............................................341
Removal and Installation .......................................343
MI & DATA LINK CONNECTORS ...........................344
Wiring Diagram .....................................................344
SERVICE DATA AND SPECIFICATIONS (SDS) ....346
Fuel Pressure ........................................................346
Idle Speed and Ignition Timing ..............................346
Mass Air Flow Sensor ...........................................346
Intake Air Temperature Sensor .............................346
Engine Coolant Temperature Sensor ....................346
Crankshaft Position Sensor (POS) .......................346
Camshaft Position Sensor (PHASE) .....................346
Heated Oxygen Sensor 1 Heater ..........................346
Heated Oxygen sensor 2 Heater ..........................346
Throttle Control Motor ...........................................346
Fuel Injector ..........................................................346
Fuel Pump .............................................................346
VQ
INDEX FOR DTC .....................................................347
DTC No. Index ......................................................347
Alphabetical Index .................................................349
PRECAUTIONS .......................................................351
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ...............................................................351
On Board Diagnostic (OBD) System of Engine ....351
Precaution .............................................................351
EC-5
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ECA
PREPARATION ....................................................... 355
Special Service Tools ........................................... 355
Commercial Service Tools .................................... 356
ENGINE CONTROL SYSTEM ................................ 357
System Diagram ................................................... 357
Multiport Fuel Injection (MFI) System .................. 358
Electronic Ignition (EI) System ............................. 360
Fuel Cut Control (at No Load and High Engine
Speed) .................................................................. 361
AIR CONDITIONING CUT CONTROL ................... 362
Input/Output Signal Chart ..................................... 362
System Description .............................................. 362
AUTOMATIC SPEED CONTROL DEVICE (ASCD) . 363
System Description .............................................. 363
Component Description ........................................ 364
CAN COMMUNICATION ........................................ 365
System Description .............................................. 365
EVAPORATIVE EMISSION SYSTEM ..................... 366
Description ........................................................... 366
Component Inspection ......................................... 369
POSITIVE CRANKCASE VENTILATION ............... 370
Description ........................................................... 370
Component Inspection ......................................... 370
NATS (NISSAN ANTI-THEFT SYSTEM) ................ 372
Description ........................................................... 372
ON BOARD DIAGNOSTIC (OBD) SYSTEM .......... 373
Introduction .......................................................... 373
Two Trip Detection Logic ...................................... 373
Emission-related Diagnostic Information .............. 373
Malfunction Indicator (MI) ..................................... 377
BASIC SERVICE PROCEDURE ............................ 381
Basic Inspection ................................................... 381
Idle Speed and Ignition Timing Check .................. 387
Procedure After Replacing ECM .......................... 389
Accelerator Pedal Released Position Learning .... 389
Throttle Valve Closed Position Learning .............. 389
Idle Air Volume Learning ...................................... 389
Fuel Pressure Check ............................................ 392
TROUBLE DIAGNOSIS .......................................... 394
Trouble Diagnosis Introduction ............................. 394
DTC Inspection Priority Chart .............................. 400
Fail-Safe Chart ..................................................... 401
Symptom Matrix Chart ......................................... 402
Engine Control Component Parts Location .......... 406
Vacuum Hose Drawing ......................................... 412
Circuit Diagram .................................................... 413
ECM Harness Connector Terminal Layout ........... 415
ECM Terminals and Reference Value .................. 415
CONSULT-II Function (ENGINE) ......................... 425
CONSULT-II Reference Value in Data Monitor Mode
. 434
Major Sensor Reference Graph in Data Monitor
Mode .................................................................... 438
TROUBLE DIAGNOSIS - SPECIFICATION VALUE . 440
Description ........................................................... 440
Testing Condition .................................................. 440
Inspection Procedure ........................................... 440
Diagnostic Procedure ........................................... 441
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-DENT .......................................................................450
Description ............................................................450
Diagnostic Procedure ...........................................450
POWER SUPPLY AND GROUND CIRCUIT ...........451
Wiring Diagram .....................................................451
Diagnostic Procedure ...........................................452
Ground Inspection ................................................457
DTC U1000, U1001 CAN COMMUNICATION LINE .458
Description ............................................................458
On Board Diagnosis Logic ....................................458
DTC Confirmation Procedure ...............................458
Wiring Diagram .....................................................459
Diagnostic Procedure ...........................................460
DTC P0011, P0021 IVT CONTROL ........................461
Description ............................................................461
CONSULT-II Reference Value in Data Monitor Mode
.461
On Board Diagnosis Logic ....................................462
DTC Confirmation Procedure ...............................462
Overall Function Check ........................................463
Diagnostic Procedure ...........................................464
Component Inspection ..........................................465
Removal and Installation ......................................465
DTC P0102, P0103 MAF SENSOR ........................466
Component Description ........................................466
CONSULT-II Reference Value in Data Monitor Mode
.466
On Board Diagnosis Logic ....................................466
DTC Confirmation Procedure ...............................467
Wiring Diagram .....................................................468
Diagnostic Procedure ...........................................469
Component Inspection ..........................................472
Removal and Installation ......................................473
DTC P0117, P0118 ECT SENSOR .........................474
Component Description ........................................474
On Board Diagnosis Logic ....................................474
DTC Confirmation Procedure ...............................475
Wiring Diagram .....................................................476
Diagnostic Procedure ...........................................477
Component Inspection ..........................................478
Removal and Installation ......................................478
DTC P0122, P0123 TP SENSOR ............................479
Component Description ........................................479
CONSULT-II Reference Value in Data Monitor Mode
.479
On Board Diagnosis Logic ....................................479
DTC Confirmation Procedure ...............................480
Wiring Diagram .....................................................481
Diagnostic Procedure ...........................................482
Component Inspection ..........................................485
Removal and Installation ......................................485
DTC P0132, P0152 HO2S1 .....................................486
Component Description ........................................486
CONSULT-II Reference Value in Data Monitor Mode
.486
On Board Diagnosis Logic ....................................486
DTC Confirmation Procedure ...............................487
Wiring Diagram .....................................................488
Diagnostic Procedure ...........................................491
EC-8 Diagnostic Procedure ...........................................648
Component Inspection ..........................................651
Removal and Installation ......................................651
DTC P2138 APP SENSOR .....................................652
Component Description ........................................652
CONSULT-II Reference Value in Data Monitor Mode
.652
On Board Diagnosis Logic ....................................652
DTC Confirmation Procedure ...............................653
Wiring Diagram .....................................................654
Diagnostic Procedure ...........................................655
Component Inspection ..........................................659
Removal and Installation ......................................659
ASCD BRAKE SWITCH ..........................................660
Component Description ........................................660
CONSULT-II Reference Value in Data Monitor Mode
.660
Wiring Diagram .....................................................661
Diagnostic Procedure ...........................................662
Component Inspection ..........................................666
ASCD INDICATOR ..................................................667
Component Description ........................................667
CONSULT-II Reference Value in Data Monitor Mode
.667
Wiring Diagram .....................................................668
Diagnostic Procedure ...........................................669
ELECTRICAL LOAD SIGNAL ................................670
Description ............................................................670
CONSULT-II Reference Value in Data Monitor Mode
.670
Diagnostic Procedure ...........................................670
ELECTRONIC CONTROLLED ENGINE MOUNT ..672
System Description ...............................................672
CONSULT-II Reference Value in Data Monitor Mode
.672
Wiring Diagram .....................................................673
Diagnostic Procedure ...........................................674
EVAP CANISTER PURGE VOLUME CONTROL
SOLENOID VALVE .................................................677
Description ............................................................677
CONSULT-II Reference Value in Data Monitor Mode
.677
Wiring Diagram .....................................................678
Diagnostic Procedure ...........................................680
Component Inspection ..........................................683
Removal and Installation ......................................683
FUEL INJECTOR ....................................................684
Component Description ........................................684
CONSULT-II Reference Value in Data Monitor Mode
.684
Wiring Diagram .....................................................685
Diagnostic Procedure ...........................................686
Component Inspection ..........................................689
Removal and Installation ......................................689
FUEL PUMP ............................................................690
Description ............................................................690
CONSULT-II Reference Value in Data Monitor Mode
.690
Wiring Diagram .....................................................691Diagnostic Procedure ............................................692
Component Inspection ..........................................695
Removal and Installation .......................................695
HO2S1 .....................................................................696
Component Description ........................................696
CONSULT-II Reference Value in Data Monitor Mode
.696
Wiring Diagram .....................................................697
Diagnostic Procedure ............................................700
Component Inspection ..........................................704
Removal and Installation .......................................705
HO2S1 HEATER ......................................................706
Description ............................................................706
CONSULT-II Reference Value in Data Monitor Mode
.706
Wiring Diagram .....................................................707
Diagnostic Procedure ............................................711
Component Inspection ..........................................713
Removal and Installation .......................................713
HO2S2 .....................................................................714
Component Description ........................................714
CONSULT-II Reference Value in Data Monitor Mode
.714
Wiring Diagram .....................................................715
Diagnostic Procedure ............................................718
Component Inspection ..........................................720
Removal and Installation .......................................722
HO2S2 HEATER ......................................................723
Description ............................................................723
CONSULT-II Reference Value in Data Monitor Mode
.723
Wiring Diagram .....................................................724
Diagnostic Procedure ............................................727
Component Inspection ..........................................729
Removal and Installation .......................................729
IAT SENSOR ...........................................................730
Component Description ........................................730
Wiring Diagram .....................................................731
Diagnostic Procedure ............................................732
Component Inspection ..........................................734
Removal and Installation .......................................734
IGNITION SIGNAL ..................................................735
Component Description ........................................735
Wiring Diagram .....................................................736
Diagnostic Procedure ............................................741
Component Inspection ..........................................746
Removal and Installation .......................................747
REFRIGERANT PRESSURE SENSOR ..................748
Component Description ........................................748
Wiring Diagram .....................................................749
Diagnostic Procedure ............................................750
Removal and Installation .......................................752
VIAS .........................................................................753
Description ............................................................753
CONSULT-II Reference Value in Data Monitor Mode
.754
Wiring Diagram .....................................................755
Diagnostic Procedure ............................................757
PREPARATION
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Commercial Service ToolsBBS005BD
Tool name Description
Quick connector
releaseRemoving fuel tube quick connectors in engine
room
(Available in SEC. 164 of PARTS CATALOG: Part
No. 16441 6N210)
Fuel filler cap adapter Checking fuel tank vacuum relief valve opening
pressure
Socket wrench Removing and installing engine coolant
temperature sensor
Oxygen sensor thread
cleanerReconditioning the exhaust system threads
before installing a new oxygen sensor. Use with
anti-seize lubricant shown below.
a: 18 mm diameter with pitch 1.5 mm for
Zirconia Oxygen Sensor
b: 12 mm diameter with pitch 1.25 mm for
Titania Oxygen Sensor
Anti-seize lubricant
i.e.: (Permatex
TM
133AR or equivalent
meeting MIL
specification MIL-A-
907)Lubricating oxygen sensor thread cleaning tool
when reconditioning exhaust system threads.
PBIC0198E
S-NT653
S-NT705
AEM488
S-NT779
ENGINE CONTROL SYSTEM
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Multiport Fuel Injection (MFI) SystemBBS005BF
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)
Camshaft position sensor (PHASE)Engine speed*
3
Piston position
Fuel injection & mixture
ratio controlFuel injector Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Heated oxygen 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
Wheel sensor
Vehicle speed*
2
Air conditioner switch
Air conditioner operation*2
EC-22
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ENGINE CONTROL SYSTEM
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 (manifold) can then better reduce CO, HC and NOx emissions. This system uses
heated oxygen 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
heated oxygen sensor 1, refer to EC-143
. 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 (manifold). Even if the switching
characteristics of heated oxygen 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 heated oxygen sensor 1 or its circuit
Insufficient activation of heated oxygen 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 heated oxygen
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 heated oxygen sensor 1 indicates whether the mixture ratio is RICH or LEAN compared
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.
PBIB2953E
ENGINE CONTROL SYSTEM
EC-23
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FUEL INJECTION TIMING
Two types of systems are used.
Sequential Multiport Fuel Injection System
Fuel is injected into each cylinder during each engine cycle according to the firing order. This system is used
when the engine is running.
Simultaneous Multiport Fuel Injection System
Fuel is injected simultaneously into all four cylinders twice each engine cycle. In other words, pulse signals of
the same width are simultaneously transmitted from the ECM.
The four fuel injectors will then receive the signals two times for each engine cycle.
This system is used when the engine is being started and/or if the fail-safe system (CPU) is operating.
FUEL SHUT-OFF
Fuel to each cylinder is cut off during deceleration or operation of the engine at excessively high speeds.
Electronic Ignition (EI) SystemBBS005BG
INPUT/OUTPUT SIGNAL CHART
*1: This signal is sent to the ECM through CAN communication line.
*2: ECM determines the start signal status by the signals of engine speed and battery voltage.
SYSTEM DESCRIPTION
Firing order: 1-3-4-2
The ignition timing is controlled by the ECM to maintain the best air-fuel ratio for every running condition of the
engine. The ignition timing data is stored in the ECM.
The ECM receives information such as the injection pulse width and camshaft position sensor signal. Comput-
ing this information, ignition signals are transmitted to the power transistor.
During the following conditions, the ignition timing is revised by the ECM according to the other data stored in
the ECM.
At starting
During warm-up
At idle
At low battery voltage
During acceleration
SEF337W
Sensor Input Signal to ECM ECM function Actuator
Crankshaft position sensor (POS)
Engine speed*
2
Piston position
Ignition timing
controlPower transistor Camshaft position sensor (PHASE)
Mass air flow sensor Amount of intake air
Engine coolant temperature sensor Engine coolant temperature
Throttle position sensor Throttle position
Accelerator pedal position sensor Accelerator pedal position
Knock sensor Engine knocking
Park/neutral position (PNP) switch Gear position
Battery
Battery voltage*
2
Wheel sensor
Vehicle speed*1