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Nissan Titan. Manual - part 187

DIAGNOSIS SYSTEM (ECM)

EC-49

< SYSTEM DESCRIPTION >

[VK56DE]

A particular trouble code can be identified by the number of four-digit numeral flashes per the following.

The length of time the 1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-sec-

onds) - OFF (0.6-seconds) cycle.

The 100th-digit numeral and lower digit numerals consist of a 0.3-seconds ON and 0.3-seconds OFF cycle.

A change from one digit numeral to another occurs at an interval of 1.0-second OFF. In other words, the later

numeral appears on the display 1.3 seconds after the former numeral has disappeared.

A change from one trouble code to another occurs at an interval of 1.8-seconds OFF.

In this way, all the detected malfunctions are classified by their DTC numbers. The DTC 0000 refers to no mal-

function. Refer to

EC-75, "DTC Index"

How to Erase Self-diagnostic Results

By performing this procedure, ECM memory is erased and the following diagnostic information is erased as

well.

• Diagnostic trouble codes

• 1st trip diagnostic trouble codes

• Freeze frame data

• 1st trip freeze frame data

• System readiness test (SRT) codes

• Test values

NOTE:

Also, if a battery terminal is disconnected, ECM memory is erased and the diagnostic information as listed

above is erased. (The amount of time required for erasing may vary from a few seconds to several hours.)
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Set ECM in Self-diagnostic results.
6. The diagnostic information has been erased from the backup memory in the ECM.

Fully depress the accelerator pedal and keep it depressed for more than 10 seconds.

7. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.

CONSULT Function

INFOID:0000000009886512

FUNCTION

*: The following emission-related diagnostic information is cleared when the ECM memory is erased.
• Diagnostic trouble codes
• 1st trip diagnostic trouble codes
• Freeze frame data
• 1st trip freeze frame data
• System readiness test (SRT) codes
• Test values

Number

Flashes

Diagnostic test mode

Function

Self Diagnostic Results

Self-diagnostic results such as 1st trip DTC, DTCs and 1st trip freeze frame data or freeze frame data
can be read and erased quickly.*

Data Monitor

Input/Output data in the ECM can be read.

Work support

This mode enables a technician to adjust some devices faster and more accurately by following the in-
dications on the CONSULT unit.

Active Test

Diagnostic Test Mode in which CONSULT drives some actuators apart from the ECMs and also shifts
some parameters in a specified range.

Ecu Identification

ECM part number can be read.

DTC Work Support

The status of system monitoring tests and the self-diagnosis status/result can be confirmed.

EC-50

< SYSTEM DESCRIPTION >

[VK56DE]

DIAGNOSIS SYSTEM (ECM)

SELF DIAGNOSTIC RESULTS MODE

Self Diagnostic Item

Regarding items of DTC and 1st trip DTC, refer to

EC-75, "DTC Index"

How to Read DTC and 1st Trip DTC

DTCs and 1st trip DTCs related to the malfunction are displayed in “Self-diag results”.

• When ECM detects a 1st trip DTC, “1t” is displayed for “TIME”.

• When ECM has detected a current DTC, “0” is displayed for “TIME”.

• If “TIME” is neither “0” nor “1t”, the DTC occurred in the past and ECM shows the number of times the vehi-

cle has been driven since the last detection of the DTC.

How to Erase DTC and 1st Trip DTC

NOTE:

• If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10

seconds and then turn it ON (engine stopped) again.

• If the DTC is not for A/T related items (see

EC-75, "DTC Index"

), skip step 1.

1. Erase DTC in TCM. Refer to

TM-36, "Introduction"

2. Select “ENGINE” with CONSULT.

3. Select “SELF-DIAG RESULTS”.

4. Touch “ERASE”. (DTC in ECM will be erased.)

Freeze Frame Data and 1st Trip Freeze Frame Data

*: The item is the same as that of 1st trip freeze frame data.

DATA MONITOR MODE

Freeze frame data

item*

Description

DIAG TROUBLE
CODE
[PXXXX]

• The engine control component part/control system has a trouble code, it is displayed as PXXXX. (Refer to

EC-75, "DTC Index"

FUEL SYS-B1

• “Fuel injection system status” at the moment a malfunction is detected is displayed.
• One mode in the following is displayed.

Mode2: Open loop due to detected system malfunction
Mode3: Open loop due to driving conditions (power enrichment, deceleration enleanment)
Mode4: Closed loop - using oxygen sensor(s) as feedback for fuel control
Mode5: Open loop - has not yet satisfied condition to go to closed loop

FUEL SYS-B2

COMBUST CONDI-
TION

• These items are displayed but are not applicable to this model.

CAL/LD VALUE [%]

• The calculated load value at the moment a malfunction is detected is displayed.

COOLANT TEMP
[

°C] or [°F]

• The engine coolant temperature at the moment a malfunction is detected is displayed.

L-FUEL TRM-B1 [%]

• “Long-term fuel trim” at the moment a malfunction is detected is displayed.
• The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule than

short-term fuel trim.

L-FUEL TRM-B2 [%]

S-FUEL TRM-B1 [%]

• “Short-term fuel trim” at the moment a malfunction is detected is displayed.
• The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel sched-

ule.

S-FUEL TRM-B2 [%]

ENGINE SPEED [rpm] • The engine speed at the moment a malfunction is detected is displayed.

VEHICL SPEED
[km/h] or [mph]

• The vehicle speed at the moment a malfunction is detected is displayed.

INT MANI PRES [kPa]
or [psi]

• These items are displayed but are not applicable to this model.

ABSOL TH-P/S
[%]

• The throttle valve opening at the moment a malfunction is detected is displayed.

B/FUEL SCHDL
[msec]

• The base fuel schedule at the moment a malfunction is detected is displayed.

INT/A TEMP SE
[

°C] or [°F]

• The intake air temperature at the moment a malfunction is detected is displayed.

DIAGNOSIS SYSTEM (ECM)

EC-51

< SYSTEM DESCRIPTION >

[VK56DE]

NOTE:

The following table includes information (items) inapplicable to this vehicle. For information (items) applicable

to this vehicle, refer to CONSULT display items.

Monitored Item

For reference values of the following items, refer to

EC-60, "CONSULT Reference Value in Data Monitor

Mode"

Monitored item

[Unit]

ECM IN-

PUT SIG-

NALS

MAIN

SIGNALS

Description

Remarks

ENG SPEED [rpm]

• Indicates the engine speed computed

from the signal of the crankshaft position
sensor (POS) and camshaft position
sensor (PHASE).

• Accuracy becomes poor if engine speed

drops below the idle rpm.

• If the signal is interrupted while the en-

gine is running, an abnormal value may
be indicated.

MAS A/F SE-B1 [V]

• The signal voltage of the mass air flow

sensor is displayed.

• When the engine is stopped, a certain

value is indicated.

• When engine is running specification

range is indicated in “SPEC”.

B/FUEL SCHDL
[ms]

• Base fuel schedule indicates the fuel in-

jection pulse width programmed into
ECM, prior to any learned on board cor-
rection.

• When engine is running specification

range is indicated in “SPEC”.

A/F ALPHA-B1 [%]

• The mean value of the air-fuel ratio feed-

back correction factor per cycle is indi-
cated.

• When the engine is stopped, a certain

value is indicated.

• When engine is running specification

range is indicated in “SPEC”.

• This data also includes the data for the

air-fuel ratio learning control.

A/F ALPHA-B2 [%]

COOLANT TEMP/
S [

°C] or [°F]

• The engine coolant temperature (deter-

mined by the signal voltage of the engine
coolant temperature sensor) is dis-
played.

• When the engine coolant temperature

sensor is open or short-circuited, ECM
enters fail-safe mode. The engine cool-
ant temperature determined by the ECM
is displayed.

A/F SEN1 (B1) [V]

• The A/F signal computed from the input

signal of the A/F sensor 1 is displayed.

HO2S2 (B1) [V]

• The signal voltage of the heated oxygen

sensor 2 is displayed.

HO2S2 (B2) [V]

HO2S2 MNTR(B1)
[RICH/LEAN]

• Display of heated oxygen sensor 2 sig-

nal:
RICH: means the amount of oxygen after
three way catalyst is relatively small.
LEAN: means the amount of oxygen af-
ter three way catalyst is relatively large.

• When the engine is stopped, a certain

value is indicated.

HO2S2 MNTR(B2)
[RICH/LEAN]

VHCL SPEED SE
[km/h] or [mph]

• The vehicle speed computed from the

vehicle speed signal sent from combina-
tion meter is displayed.

BATTERY VOLT
[V]

• The power supply voltage of ECM is dis-

played.

ACCEL SEN 1 [V]

• The accelerator pedal position sensor

signal voltage is displayed.

• ACCEL SEN 2 signal is converted by

ECM internally. Thus, it differs from ECM
terminal voltage signal.

ACCEL SEN 2 [V]

TP SEN 1-B1

• The throttle position sensor signal volt-

age is displayed.

• TP SEN 2-B1 signal is converted by

ECM internally. Thus, it differs from ECM
terminal voltage signal.

TP SEN 2-B1

FUEL T/TMP SE
[

°C] or [°F]

• The fuel temperature (determined by the

signal voltage of the fuel tank tempera-
ture sensor) is displayed.

EC-52

< SYSTEM DESCRIPTION >

[VK56DE]

DIAGNOSIS SYSTEM (ECM)

EVAP SYS PRES
[V]

• The signal voltage of EVAP control sys-

tem pressure sensor is displayed.

FUEL LEVEL SE
[V]

• The signal voltage of the fuel level sen-

sor 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] comput-

ed by ECM according to the accelerator
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.

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: Lighting switch is in 2nd position.
OFF: Lighting switch is OFF.

IGNITION SW
[ON/OFF]

• Indicates [ON/OFF] condition from igni-

tion switch signal.

HEATER FAN SW
[ON/OFF]

• Indicates [ON/OFF] condition from heat-

er 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 [BT-
DC]

• 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 val-

ue of the current air flow divided by peak
air flow.

MASS AIRFLOW
[g/s]

• Indicates the mass air flow computed by

ECM according to the signal voltage of
the mass air flow sensor.

PURG VOL C/V [%]

• Indicates the EVAP canister purge vol-

ume control solenoid valve control value
computed by the ECM according to the
input signals.

• The opening becomes larger as the val-

ue increases.

INT/V TIM(B1)
[

°CA]

• Indicates [

°CA] of intake camshaft ad-

vanced angle.

INT/V TIM(B2)
[

°CA]

Monitored item

[Unit]

ECM IN-

PUT SIG-

NALS

MAIN

SIGNALS

Description

Remarks

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