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Infiniti M35/M45 Y50. Manual - part 399

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-69

[VQ35DE]

WITH GST

The emission related diagnostic information in the ECM can be erased by selecting Service $04 with GST.

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

EC-16, "INDEX FOR DTC"

), skip step 2.

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.

Perform

AT-40, "OBD-II Diagnostic Trouble Code (DTC)"

. (The DTC in TCM will be erased)

Select Service $04 with GST (Generic Scan Tool).

No Tools

NOTE:
If the DTC is not for AT related items (see

EC-16, "INDEX FOR DTC"

), skip step 2.

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.

Perform

AT-40, "OBD-II Diagnostic Trouble Code (DTC)"

. (The DTC in the TCM will be erased.)

Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal. Refer to

EC-71, "HOW TO SWITCH DIAGNOSTIC TEST MODE"

●

If the battery is disconnected, the emission-related diagnostic information will be lost within 24
hours.

●

The following data are 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

SCIA5671E

EC-70

[VQ35DE]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

–

Test values

Actual work procedures are explained using a DTC as an example. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.

Malfunction Indicator Lamp (MIL)

NBS004SO

DESCRIPTION

The MIL is located on the instrument panel.

The MIL will light up when the ignition switch is turned ON with-
out the engine running. This is a bulb check.
If the MIL does not light up, refer to

DI-39, "WARNING LAMPS"

or see

EC-714, "MIL AND DATA LINK CONNECTOR"

When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.

ON BOARD DIAGNOSTIC SYSTEM FUNCTION

The on board diagnostic system has the following three functions.

When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by means
of operating fail-safe function.
The fail-safe function also operates when above diagnoses except MIL circuit are detected and demands the
driver to repair the malfunction.

SEF217U

Diagnostic Test
Mode

KEY and ENG.
Status

Function

Explanation of Function

Mode I

Ignition switch in
ON position

Engine stopped

BULB CHECK

This function checks the MIL bulb for damage (blown,
open circuit, etc.).
If the MIL does not come on, check MIL circuit.

Engine running

MALFUNCTION
WARNING

This is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MIL will light up to inform the driver
that a malfunction has been detected.
The following malfunctions will light up or blink the MIL in
the 1st trip.

●

Misfire (Possible three way catalyst damage)

●

One trip detection diagnoses

Mode II

Ignition switch in
ON position

Engine stopped

SELF-DIAGNOSTIC
RESULTS

This function allows DTCs and 1st trip DTCs to be read.

Engine operating condition in fail-safe mode

Engine speed will not rise more than 2,500 rpm due to the fuel cut

ON BOARD DIAGNOSTIC (OBD) SYSTEM

EC-71

[VQ35DE]

MIL Flashing Without DTC

When any SRT codes are not set, MIL may flash without DTC. For the details, refer to

EC-63, "How to Display

SRT Status"

HOW TO SWITCH DIAGNOSTIC TEST MODE

NOTE:

●

It is better to count the time accurately with a clock.

●

It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.

●

Always ECM returns to Diagnostic Test Mode I after ignition switch is turned OFF.

How to Set Diagnostic Test Mode II (Self-diagnostic Results)

Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.

Repeat the following procedure quickly five times within 5 seconds.

Fully depress the accelerator pedal.

Fully release the accelerator pedal.

Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts
blinking.

NOTE:
Do not release the accelerator pedal for 10 seconds if MIL may start blinking on the halfway of this
10 seconds. This blinking is displaying SRT status and is continued for another 10 seconds. For
the details, refer to

EC-63, "How to Display SRT Status"

Fully release the accelerator pedal.
ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).

NOTE:
Wait until the same DTC (or 1st trip DTC) appears to confirm all DTCs certainly.

How to Erase Diagnostic Test Mode II (Self-diagnostic Results)

Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to

EC-71, "How to Set Diagnostic Test

Mode II (Self-diagnostic Results)"

Fully depress the accelerator pedal and keep it for more than 10 seconds.
The emission-related diagnostic information has been erased from the backup memory in the ECM.

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

DIAGNOSTIC TEST MODE I — BULB CHECK

In this mode, the MIL on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to

DI-

39, "WARNING LAMPS"

or see

EC-714, "MIL AND DATA LINK CONNECTOR"

DIAGNOSTIC TEST MODE I — MALFUNCTION WARNING

This DTC number is clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)

PBIB0092E

MIL

Condition

When the malfunction is detected.

OFF

No malfunction.

EC-72

[VQ35DE]

ON BOARD DIAGNOSTIC (OBD) SYSTEM

DIAGNOSTIC TEST MODE II — SELF-DIAGNOSTIC RESULTS

In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MIL as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MIL does not illuminate in diagnostic test
mode I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MIL
illuminates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are
displayed, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These uniden-
tified codes can be identified by using the CONSULT-II or GST. A DTC will be used as an example for how to
read a code.

A particular trouble code can be identified by the number of four-digit numeral flashes. The “zero” is indicated
by the number of ten flashes. The “A” is indicated by the number of eleven flash. The length of time the
1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-second) - OFF (0.6-second)
cycle.
The 100th-digit numeral and lower digit numerals consist of a 0.3-second ON and 0.3-second 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-second OFF.
In this way, all the detected malfunctions are classified by their DTC numbers. The DTC 0000 refers to no mal-
function. (See

EC-16, "INDEX FOR DTC"

)

How to Erase Diagnostic Test Mode II (Self-diagnostic Results)

The DTC can be erased from the back up memory in the ECM by depressing accelerator pedal. Refer to

EC-

71, "How to Erase Diagnostic Test Mode II (Self-diagnostic Results)"

●

If the battery is disconnected, the DTC will be lost from the backup memory within 24 hours.

●

Be careful not to erase the stored memory before starting trouble diagnoses.

PBIB3005E

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