light INFINITI M35 2007 Factory Service Manual

TROUBLE DIAGNOSIS
EC-821
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Revision: 2007 April2007 M35/M4538 G/BFuel pump control module
(FPCM) check[When cranking engine]Approximately 0V
[Engine is running]
Warm-up condition

Idle speed4 - 6V
39 B/RFuel pump control module
(FPCM)[When cranking engine]0 - 0.5V
[Engine is running]

Warm-up condition

Idle speed8 - 12V
45 VEVAP canister purge vol-
ume control solenoid valve[Engine is running]

Idle speed

Accelerator pedal: Not depressed even
slightly, after engine startingBATTERY VOLTAGE
(11 - 14V)
[Engine is running]

Engine speed: About 2,000 rpm (More than
100 seconds after starting engine)BATTERY VOLTAGE
(11 - 14V)
46
60
61
62
65
79
80
81L/O
V/W
P
Y/R
BR/R
GR/R
GR/B
G/RIgnition signal No. 7
Ignition signal No. 5
Ignition signal No. 3
Ignition signal No. 1
Ignition signal No. 8
Ignition signal No. 6
Ignition signal No. 4
Ignition signal No. 2[Engine is running]

Warm-up condition

Idle speed
NOTE:
The pulse cycle changes depending on rpm
at idle0 - 0.2V
[Engine is running]

Warm-up condition

Engine speed: 2,000 rpm0.1 - 0.4V
47 GSensor power supply
(Throttle position sensor)[Ignition switch: ON]Approximately 5V
48 BRSensor power supply
(EVAP control system pres-
sure sensor)[Ignition switch: ON]Approximately 5V
49 B/YSensor power supply
(Refrigerant pressure sen-
sor, Battery current sensor)[Ignition switch: ON]Approximately 5V TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
SEC990C
SEC991C
PBIB0044E
PBIB0045E

EC-824
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TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
83 PSensor ground
(APP sensor 2)[Engine is running]
Warm-up condition

Idle speedApproximately 0V
85 V Data link connector[Ignition switch: ON]

CONSULT-II or GST: DisconnectedApproximately 5V - Battery volt-
age (11 - 14V)
86 P CAN communication line[Ignition switch: ON]Approximately 1.1 - 2.3V
Output voltage varies with the
communication status.
90 LSensor power supply
(APP sensor 1)[Ignition switch: ON]Approximately 5V
91 BRSensor power supply
(APP sensor 2)[Ignition switch: ON]Approximately 5V
94 L CAN communication line[Ignition switch: ON]Approximately 2.6 - 3.2V
Output voltage varies with the
communication status.
98 RAccelerator pedal position
sensor 2[Ignition switch: ON]

Engine: Stopped

Accelerator pedal: Fully released0.20 - 0.55V
[Ignition switch: ON]

Engine: Stopped

Accelerator pedal: Fully depressed1.85 - 2.40V
99 G/YICC steering switch
(models with ICC system)[Ignition switch: ON]

ICC steering switch: OFFApproximately 4.3V
[Ignition switch: ON]

MAIN switch: PressedApproximately 0V
[Ignition switch: ON]

CANCEL switch: PressedApproximately 1.3V
[Ignition switch: ON]

RESUME/ACCELERATE switch: PressedApproximately 3.7V
[Ignition switch: ON]

SET/COAST switch: PressedApproximately 3V
[Ignition switch: ON]

DISTANCE switch: PressedApproximately 2.2V
99 YASCD steering switch
(models with ASCD system)[Ignition switch: ON]

ASCD steering switch: OFFApproximately 4V
[Ignition switch: ON]

MAIN switch: PressedApproximately 0V
[Ignition switch: ON]

CANCEL switch: PressedApproximately 1V
[Ignition switch: ON]

RESUME/ACCELERATE switch: PressedApproximately 3V
[Ignition switch: ON]

SET/COAST switch: PressedApproximately 2V
101 V/R Stop lamp switch[Ignition switch: OFF]

Brake pedal: Fully releasedApproximately 0V
[Ignition switch: OFF]

Brake pedal: Slightly depressedBATTERY VOLTAGE
(11 - 14V) TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)

TROUBLE DIAGNOSIS
EC-825
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Revision: 2007 April2007 M35/M45
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
*: Before measuring the terminal voltage, confirm that the battery is fully charged. Refer to SC-5, "
SPECIFIC GRAVITY CHECK" . 102 G PNP switch[Ignition switch: ON]

Selector lever: P or NApproximately 0V
[Ignition switch: ON]

Selector lever: Except aboveBATTERY VOLTAGE
(11 - 14V)
104 O Throttle control motor relay[Ignition switch: OFF]BATTERY VOLTAGE
(11 - 14V)
[Ignition switch: ON]0 - 1.0V
106 LGAccelerator pedal position
sensor 1[Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully released0.4 - 1.1V
[Ignition switch: ON]

Engine stopped

Accelerator pedal: Fully depressed3.7 - 4.8V
107 V/WFuel tank temperature sen-
sor[Engine is running]Approximately 0 - 4.8V
Output voltage varies with fuel
tank temperature.
108 BRICC brake switch (models
witch ICC system)
ASCD brake switch (models
witch ASCD system)[Ignition switch: ON]

Brake pedal: Slightly depressedApproximately 0V
[Ignition switch: ON]

Brake pedal: Fully releasedBATTERY VOLTAGE
(11 - 14V)
109 L Ignition switch[Ignition switch: OFF]0V
[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
111 S BECM relay
(Self shut-off)[Engine is running]
[Ignition switch: OFF]

For a few seconds after turning ignition
switch OFF0 - 1.5V
[Ignition switch: OFF]

More than a few seconds after turning igni-
tion switch OFFBATTERY VOLTAGE
(11 - 14V)
113 GR Fuel pump relay[Ignition switch: ON]

For 1 second after turning ignition switch ON
[Engine is running]0 - 1.5V
[Ignition switch: ON]

More than 1 second after turning ignition
switch ONBATTERY VOLTAGE
(11 - 14V)
11 5
11 6B
BECM ground[Engine is running]

Idle speedBody ground
11 7 G R / LEVAP canister vent control
valve[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
11 9
120R
RPower supply for ECM[Ignition switch: ON]BATTERY VOLTAGE
(11 - 14V)
121 LPower supply for ECM
(Back-up)[Ignition switch: OFF]BATTERY VOLTAGE
(11 - 14V) TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)

TROUBLE DIAGNOSIS
EC-831
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Revision: 2007 April2007 M35/M45THRTL SEN 1 [V]××
The throttle position sensor signal voltage
is displayed.
THRTL SEN 2 signal is converted by
ECM internally. Thus, it differs from ECM
terminal voltage signal. THRTL SEN 2 [V]×
FUEL T/TMP SE
[°C] or [°F]×

The fuel temperature (determined by the
signal voltage of the fuel tank tempera-
ture sensor) is displayed.
INT/A TEMP SE
[°C] or [°F]××

The intake air temperature (determined
by the signal voltage of the intake air tem-
perature sensor) is indicated.
EVAP SYS PRES
[V]×

The signal voltage of EVAP control sys-
tem pressure sensor is displayed.
FPCM DR VOLT
[V]

The voltage between fuel pump and
FPCM is displayed.
FUEL LEVEL SE
[V]×

The signal voltage of the fuel level sensor
is displayed.
START SIGNAL
[ON/OFF]××

Indicates start signal status [ON/OFF]
computed by the ECM according to the
signals of engine speed and battery volt-
age.

After starting the engine, [OFF] is dis-
played regardless of the starter signal.
CLSD THL POS
[ON/OFF]××

Indicates idle position [ON/OFF] com-
puted by ECM according to the accelera-
tor pedal position sensor signal.
AIR COND SIG
[ON/OFF]××

Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF]××

Indicates [ON/OFF] condition from the
park/neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××

[ON/OFF] condition of the power steering
system (determined by the signal voltage
of the power steering pressure sensor
signal) is indicated.
LOAD SIGNAL
[ON/OFF]××

Indicates [ON/OFF] condition from the
electrical load signal.
ON: Rear window defogger switch is ON
and/or lighting switch is in 2nd position.
OFF: Both rear window defogger switch
and lighting switch are OFF.
IGNITION SW
[ON/OFF]×

Indicates [ON/OFF] condition from igni-
tion switch signal.
HEATER FAN SW
[ON/OFF]×

Indicates [ON/OFF] condition from the
heater fan switch signal.
BRAKE SW
[ON/OFF]×

Indicates [ON/OFF] condition from the
stop lamp switch signal.
INJ PULSE-B1
[msec]×

Indicates the actual fuel injection pulse
width compensated by ECM according to
the input signals.
When the engine is stopped, a certain
computed value is indicated.
INJ PULSE-B2
[msec]
IGN TIMING
[BTDC]×

Indicates the ignition timing computed by
ECM according to the input signals.
When the engine is stopped, a certain
value is indicated.
CAL/LD VALUE [%]

“Calculated load value” indicates the
value of the current air flow divided by
peak air flow. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS
EC-835
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Revision: 2007 April2007 M35/M45
ACTIVE TEST MODE
Test Item
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION

Engine: Return to the original
trouble condition

Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Fuel injector

Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING

Engine: Return to the original
trouble condition

Timing light: Set

Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Perform Idle Air Volume Learning.
POWER BAL-
ANCE

Engine: After warming up, idle
the engine.

A/C switch OFF

Selector lever: P or N

Cut off each fuel injector signal
one at a time using CONSULT-II.Engine runs rough or dies.

Harness and connectors

Compression

Fuel injector

Power transistor

Spark plug

Ignition coil
ENG COOLANT
TEMP

Engine: Return to the original
trouble condition

Change the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Engine coolant temperature sen-
sor

Fuel injector
FUEL PUMP
RELAY

Ignition switch: ON (Engine
stopped)

Turn the fuel pump relay ON and
OFF using CONSULT-II and lis-
ten to operating sound.Fuel pump relay makes the operat-
ing sound.
Harness and connectors

Fuel pump relay
VIAS SOL VALVE

Ignition switch: ON

Turn solenoid valve ON and OFF
with CONSULT-II and listen to
operating sound.Solenoid valve makes an operating
sound.
Harness and connectors

Solenoid valve
PURG VOL
CONT/V

Engine: After warming up, run
engine at 1,500 rpm.

Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-II.Engine speed changes according to
the opening percent.
Harness and connectors

Solenoid valve
FUEL/T TEMP
SEN

Change the fuel tank temperature using CONSULT-II.
VENT CON-
TROL/V

Ignition switch: ON (Engine
stopped)

Turn solenoid valve ON and OFF
with the CONSULT-II and listen
to operating sound.Solenoid valve makes an operating
sound.
Harness and connectors

Solenoid valve
FPCM

Engine: Returns to the original
trouble condition

Select “LOW” and “HI” with CON-
SULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

FPCM
V/T ASSIGN
ANGLE

Engine: Return to the original
trouble condition

Change intake valve timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Intake valve timing control sole-
noid valve

TROUBLE DIAGNOSIS
EC-841
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Revision: 2007 April2007 M35/M45
CONSULT-II Reference Value in Data MonitorNBS005AP
Remarks:

Specification data are reference values.

Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show the specification data in
spite of the ignition timing not being adjusted to the specification data. This IGN TIMING monitors the data calculated by the ECM
according to the signals input from the camshaft position sensor and other ignition timing related sensors.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED

Run engine and compare CONSULT-II value with the tachometer indication.Almost the same speed as
the tachometer indication.
MAS A/F SE-B1 See EC-847, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
B/FUEL SCHDL See EC-847, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
A/F ALPHA-B1
A/F ALPHA-B2See EC-847, "
TROUBLE DIAGNOSIS - SPECIFICATION VALUE" .
COOLAN TEMP/S

Engine: After warming up More than 70°C (158°F)
A/F SEN1 (B1)
A/F SEN1 (B2)

Engine: After warming up Maintaining engine speed at 2,000 rpm Fluctuates around 1.5 V
HO2S2 (B1)
HO2S2 (B2)

Revving engine from idle to 3,000 rpm quickly after the following conditions
are met.
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no load0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)LEAN ←→ RICH
VHCL SPEED SE

Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as
speedometer indication
BATTERY VOLT

Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN 1
ACCEL SEN 2*
1
Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.4 - 1.1V
Accelerator pedal: Fully depressed 3.7 - 4.8V
THRTL SEN 1
THRTL SEN 2*
1

Ignition switch: ON
(Engine stopped)

Selector lever: DAccelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
EVAP SYS PRES

Ignition switch: ON Approx. 1.8 - 4.8V
START SIGNAL

Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG

Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
P/N POSI SW

Ignition switch: ONSelector lever: P or N ON
Selector lever: Except above OFF
PW/ST SIGNAL

Engine: After warming up, idle
the engineSteering wheel: Not being turned
(Forward direction)OFF
Steering wheel: Being turned ON
LOAD SIGNAL

Ignition switch: ONRear window defogger switch: ON
and/or
Lighting switch: 2ND positionON
Rear window defogger switch and light-
ing switch: OFFOFF
IGNITION SW

Ignition switch: ON → OFF → ON ON → OFF → ON
HEATER FAN SW

Engine: After warming up, idle
the engineHeater fan switch: ON ON
Heater fan switch: OFF OFF

EC-842
[VK45DE]
TROUBLE DIAGNOSIS
Revision: 2007 April2007 M35/M45
BRAKE SW
Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
INJ PULSE-B1
INJ PULSE-B2

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle 2.0 - 3.0 msec
2,000 rpm 1.9 - 2.9 msec
IGN TIMING

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle 7° - 17° BTDC
2,000 rpm 25° - 45° BTDC
CAL/LD VALUE

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle 2.0 - 6.0 g·m/s
2,500 rpm 7.0 - 20.0 g·m/s
PURG VOL C/V

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle
(Accelerator pedal: Not depressed even
slightly, after engine starting.)0%
2,000 rpm —
INT/V TIM (B1)
INT/V TIM (B2)

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle−5° - 5°CA
2,000 rpm Approx. 0° - 20°CA
INT/V SOL (B1)
INT/V SOL (B2)

Engine: After warming up

Selector lever: P or N

Air conditioner switch: OFF

No loadIdle 0% - 2%
2,000 rpm Approx. 25% - 50%
VIAS S/V

Selector lever: P or N
ON

Engine speed: More than 5,000 rpm

Selector lever: Except P or N

Engine speed: Less than 5,000 rpmOFF
AIR COND RLY

Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates)ON
FUEL PUMP RLY

For 1 seconds after turning ignition switch: ON

Engine running or crankingON

Except above OFF
FPCM

Engine: Cranking HI

Engine: Idle

Engine coolant temperature: More than 10°C (50°F)LOW
VENT CONT/V

Ignition switch: ON OFF
THRTL RELAY

Ignition switch: ON ON MONITOR ITEM CONDITION SPECIFICATION

TROUBLE DIAGNOSIS
EC-843
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Revision: 2007 April2007 M35/M45
HO2S2 HTR (B1)
HO2S2 HTR (B2)

Engine speed: Below 3,600 rpm after the following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at
idle for 1 minute under no loadON

Engine speed: Above 3,600 rpm OFF
I/P PULLY SPD

Vehicle speed: More than 20 km/h (12 MPH)Almost the same speed as
the tachometer indication
VEHICLE SPEED

Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as
the speedometer indication
TRVL AFTER MIL

Ignition switch: ONVehicle has traveled after MIL has turned
ON.0 - 65,535 km
(0 - 40,723 miles)
A/F S1 HTR (B1)
A/F S1 HTR (B2)

Engine: After warming up, idle the engine 0 - 100%
AC PRESS SEN

Engine: Idle

Both A/C switch and blower fan switch: ON (Compressor operates)1.0 - 4.0V
VHCL SPEED SE

Turn drive wheels and compare CONSULT-II value with the speedometer
indication.Almost the same speed as
the speedometer indication
SET VHCL SPD

Engine: Running ASCD: OperatingThe preset vehicle speed is
displayed
MAIN SW

Ignition switch: ONMAIN switch: Pressed ON
MAIN switch: Released OFF
CANCEL SW

Ignition switch: ONCANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW

Ignition switch: ONRESUME/ACCELERATE switch:
PressedON
RESUME/ACCELERATE switch:
ReleasedOFF
SET SW

Ignition switch: ONSET/COAST switch: Pressed ON
SET/COAST switch: Released OFF
BRAKE SW1
(ICC/ASCD brake
switch)

Ignition switch: ONBrake pedal: Fully released ON
Brake pedal: Slightly depressed OFF
BRAKE SW2
(Stop lamp switch)

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
DIST SW

Ignition switch: ONDISTANCE switch: Pressed ON
DISTANCE switch: Released OFF
CRUISE LAMP

Ignition switch: ONMAIN switch: Pressed at the 1st time →
at the 2nd timeON → OFF
SET LAMP

MAIN switch: ON

When vehicle speed is between
40 km/h (25 MPH) and 144 km/h
(89 MPH)ASCD: Operating ON
ASCD: Not operating OFF
FAN DUTY

Engine: Running 0 - 100%
ALT DUTY

Engine: Idle 0 - 80%
BAT CUR SEN

Engine speed: Idle

Battery: Fully charged*2

Selector lever: P or N

Air conditioner switch: OFF

No loadApprox. 2,600 - 3,500mV MONITOR ITEM CONDITION SPECIFICATION

TROUBLE DIAGNOSIS - SPECIFICATION VALUE
EC-847
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Revision: 2007 April2007 M35/M45
TROUBLE DIAGNOSIS - SPECIFICATION VALUEPFP:00031
DescriptionNBS005AR
The specification (SP) value indicates the tolerance of the value that is displayed in “DATA MONITOR (SPEC)”
mode of CONSULT-II during normal operation of the Engine Control System. When the value in “DATA MONI-
TOR (SPEC)” mode is within the SP value, the Engine Control System is confirmed OK. When the value in
“DATA MONITOR (SPEC)” mode is NOT within the SP value, the Engine Control System may have one or
more malfunctions.
The SP value is used to detect malfunctions that may affect the Engine Control System, but will not light the
MIL.
The SP value will be displayed for the following three items:

B/FUEL SCHDL (The fuel injection pulse width programmed into ECM prior to any learned on board cor-
rection)

A/F ALPHA-B1/B2 (The mean value of air-fuel ratio feedback correction factor per cycle)

MAS A/F SE-B1 (The signal voltage of the mass air flow sensor)
Testing ConditionNBS005AS

Vehicle driven distance: More than 5,000 km (3,107 miles)

Barometric pressure: 98.3 - 104.3 kPa (1.003 - 1.064 kg/cm2 , 14.25 - 15.12 psi)

Atmospheric temperature: 20 - 30°C (68 - 86°F)

Engine coolant temperature: 75 - 95°C (167 - 203°F)

Engine speed: Idle

Transmission: Warmed-up
–After the engine is warmed up to normal operating temperature, drive vehicle until “ATF TEMP SE 1” (A/T
fluid temperature sensor signal) indicates more than 60°C (140°F).

Electrical load: Not applied
–Rear window defogger switch, air conditioner switch, lighting switch are OFF. Steering wheel is straight
ahead.
Inspection ProcedureNBS005AT
NOTE:
Perform “DATA MONITOR (SPEC)” mode in maximum scale display.
1. Perform EC-780, "
Basic Inspection" .
2. Confirm that the testing conditions indicated above are met.
3. Select “B/FUEL SCHDL”, “A/F ALPHA-B1”, “A/F ALPHA-B2”
and “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode with
CONSULT-II.
4. Make sure that monitor items are within the SP value.
5. If NG, go to EC-848, "
Diagnostic Procedure" .
SEF601Z

DTC U1000, U1001 CAN COMMUNICATION LINE
EC-865
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Revision: 2007 April2007 M35/M45
DTC U1000, U1001 CAN COMMUNICATION LINEPFP:23710
DescriptionNBS005B0
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
On Board Diagnosis LogicNBS005B1
*1: This self-diagnosis has the one trip detection logic.
*2: The MIL will not light up for this diagnosis.
DTC Confirmation ProcedureNBS005B2
1. Turn ignition switch ON and wait at least 3 seconds.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. If 1st trip DTC is detected, go to EC-867, "
Diagnostic Procedure" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
U1000*
1
1000*1
CAN communication lineWhen ECM is not transmitting or receiving CAN
communication signal of OBD (emission-related
diagnosis) for 2 seconds or more.

Harness or connectors
(CAN communication line is open or
shorted)
U1001*
2
1001*2
When ECM is not transmitting or receiving CAN
communication signal other than OBD (emission-
related diagnosis) for 2 seconds or more.