ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-95
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
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The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. The MI will not
light up (two trip detection logic). If the same malfunction is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are stored in the ECM memory and the MI lights up. In other words,
the DTC is stored in the ECM memory and the MI lights up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. For malfunctions that blink or light up the MI during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
Procedures for clearing the DTC and the 1st trip DTC from the ECM memory are described in “HOW TO
ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION”.
For malfunctions in which 1st trip DTCs are displayed, refer to “EMISSION-RELATED DIAGNOSTIC INFOR-
MATION ITEMS”. These items are required by legal regulations to continuously monitor the system/compo-
nent. In addition, the items monitored non-continuously are also displayed on CONSULT-III.
1st trip DTC is specified in Service $07 of ISO 15031-5. 1st trip DTC detection occurs without lighting up the
MI and therefore does not warn the driver of a malfunction. However, 1st trip DTC detection will not prevent
the vehicle from being tested, for example during Inspection/Maintenance (I/M) tests.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step 2, refer to EC-18, "
Work Flow". Then perform DTC CONFIR-
MATION PROCEDURE or Component Function Check to try to duplicate the malfunction. If the malfunction is
duplicated, the item requires repair.
Freeze Frame Data and 1st Trip Freeze Frame Data
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, absolute throttle position, base
fuel schedule and intake air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-III or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-III screen, not on the GST.
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MI on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
For example, the EGR malfunction (Priority: 2) was detected and the freeze frame data was stored in the 2nd
trip. After that when the misfire (Priority: 1) is detected in another trip, the freeze frame data will be updated
from the EGR malfunction to the misfire. The 1st trip freeze frame data is updated each time a different mal-
function is detected. There is no priority for 1st trip freeze frame data. However, once freeze frame data is
stored in the ECM memory, 1st trip freeze data is no longer stored (because only one freeze frame data or 1st
trip freeze frame data can be stored in the ECM). If freeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame data (along with the DTCs) are cleared when the ECM mem-
ory is erased. Procedures for clearing the ECM memory are described in “HOW TO ERASE EMISSION-
RELATED DIAGNOSTIC INFORMATION”.
How to Read DTC and 1st Trip DTC
With CONSULT-III
With GST
CONSULT-III or GST (Generic Scan Tool) Examples: P0340, P1148, 1706, etc.
These DTCs are prescribed by ISO 15031-5.
Priority Items
1Freeze frame data Misfire — DTC: P0300 - P0304
Fuel Injection System Function — DTC: P0171, P0172
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data
EC-96
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
(CONSULT-III also displays the malfunctioning component or system.)
No Tools
The number of blinks of the MI in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0340, 1148, 1706, etc.
These DTCs are controlled by NISSAN.
1st trip DTC No. is the same as DTC No.
Output of a DTC indicates a malfunction. However, GST or the Diagnostic Test Mode II do not indi-
cate whether the malfunction is still occurring or has occurred in the past and has returned to nor-
mal. CONSULT-III can identify malfunction status as shown below. Therefore, using CONSULT-III (if
available) is recommended.
DTC or 1st trip DTC of a malfunction is displayed in “SELF-DIAGNOSTIC RESULTS” mode of CONSULT-III.
Time data indicates how many times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
How to Erase DTC and 1st Trip DTC
With CONSULT-III
The emission related diagnostic information in the ECM can be erased by selecting “All Erase” in the “Descrip-
tion” of “FINAL CHECK” mode with CONSULT-III.
With GST
NOTE:
If the DTC is not for A/T related items (see EC-361, "
DTCIndex") skip step 2.
The emission related diagnostic information in the ECM can be erased by selecting Service $04 with GST.
1. 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.
2. Perform TM-35
. (The DTC in TCM will be erased)
3. Select Service $04 with GST (Generic Scan Tool).
No Tools
NOTE:
If the DTC is not for A/T related items (see EC-361, "
DTCIndex") skip step 2.
1. 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.
2. Perform TM-35
. (The DTC in TCM will be erased)
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal.
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
- 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.
SYSTEM READINESS TEST (SRT) CODE
System Readiness Test (SRT) code is specified in Service $01 of ISO 15031-5.
As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of
SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and com-
ponents. Completion must be verified in order for the emissions inspection to proceed.
If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use
the information in this Service Manual to set the SRT to “CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT
status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains
“CMPLT” until the self-diagnosis memory is erased.
Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's
normal driving pattern; the SRT will indicate “INCMP” for these items.
NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM mem-
ory power supply is interrupted for several hours.
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-99
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
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Selecting “SRT STATUS” in “DTC CONFIRMATION” mode with CONSULT-III.
For items whose SRT codes are set, a “CMPLT” is displayed on the CONSULT-III screen; for items whose
SRT codes are not set, “INCMP” is displayed.
WITH GST
Selecting Service $01 with GST (Generic Scan Tool)
NO TOOLS
A SRT code itself can not be displayed while only SRT status can be.
1. Turn ignition switch ON and wait 20 seconds.
2. SRT status is indicated as shown below.
When all SRT codes are set, MI lights up continuously.
When any SRT codes are not set, MI will flash periodically for 10 seconds.
MALFUNCTION INDICATOR (MI)
Description
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
If the MI does not light up, refer to EC-324, "
Component Func-
tion Check".
2. When the engine is started, the MI should go off.
If the MI 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 four functions.
*1 “How to Read DTC and 1st Trip DTC” *2 “How to Display SRT Status” *3 “How to Set SRT Code”
PBIB2317E
SAT652J
EC-100
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
MI Flashing Without DTC
If the ECM is in Diagnostic Test Mode II, MI may flash when engine is running. In this case, check ECM diag-
nostic test mode. How to switch the diagnostic test function modes, and details of the above functions are
described later.
The following emission-related diagnostic information is cleared when the ECM memory is erased.
Diagnostic trouble code
1st trip diagnostic trouble code
Freeze frame data
1st trip freeze frame data
System readiness test (SRT) codes
Test values
Diagnostic Test Mode I — Bulb Check
In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to EC-
324, "Component Function Check".
Diagnostic Test Mode I — Malfunction Warning
This DTC number is clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)
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 MI as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MI 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 MI illumi-
Diagnostic Test
ModeKEY and ENG.
StatusFunction Explanation of Function
Mode I Ignition switch in
ON position
Engine stoppedBULB CHECK This function checks the MI bulb for damage (blown, open
circuit, etc.).
If the MI does not come on, check MI circuit.
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When a malfunction is de-
tected twice in two consecutive driving cycles (two trip de-
tection logic), the MI will light up to inform the driver that a
malfunction has been detected.
The following malfunctions will light up or blink the MI in the
1st trip.
Misfire (Possible three way catalyst damage)
One trip detection diagnoses
Mode II Ignition switch in
ON position
Engine stoppedSELF-DIAGNOSTIC
RESULTSThis function allows DTCs and 1st trip DTCs to be read.
Engine running HEATED OXYGEN SENSOR 1
MONITORThis function allows the fuel mixture condition (lean or rich),
monitored by heated oxygen sensor 1, to be read.
MI Condition
ON When the malfunction is detected.
OFF No malfunction.
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-101
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
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nates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are dis-
played, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These unidentified
codes can be identified by using the CONSULT-III 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 as follows.
The length of time the 1,000th-digit numeral flashes on and off is 1.2 seconds consisting of an ON (0.6-sec-
ond) - 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-361, "
DTCIndex")
Diagnostic Test Mode II — Heated oxygen sensor 1 monitor
In this mode, the MI displays the condition of the fuel mixture (lean or rich) which is monitored by the heated
oxygen sensor 1.
*: Maintains conditions just before switching to open loop.
To check the heated oxygen sensor 1 function, start engine in the Diagnostic Test Mode II and warm it up until
engine coolant temperature indicator points to the middle of the gauge.
Nest run engine at about 2,000 rpm for about 2 minutes under no load conditions. Then make sure that the MI
comes ON more than 5 times within 1 seconds with engine running at 2,000 rpm under no load.
Number 0 123456789 A B C D E F
Flashes 10 123456789 11 12 13 14 15 16
PBIB3005E
MI Fuel mixture condition in the exhaust gas Air fuel ratio feedback control condition
ON Lean
Closed loop system
OFF Rich
*Remains ON or OFF Any condition Open loop system
EC-102
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
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)
1. Confirm that accelerator pedal is fully released, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
- Fully depress the accelerator pedal.
- Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MI starts
blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MI may start blinking on the halfway of this
10 seconds. This blinking is displaying SRT status and is continued for another 10 seconds.
4. 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 SET DIAGNOSTIC TEST MODE II (HEATE OXYGEN SENSOR 1 MONITOR)
1. Set ECM in Diagnostic Test Mode II (Self-diagnostic results).
Refer to “How to Set Diagnostic Test Mode II (Self-diagnostic Results)”.
2. Start Engine.
ECM has entered to Diagnostic Test Mode II (Heated oxygen sensor 1 monitor).
HOW TO ERASE DIAGNOSTIC TEST MODE II (SELF-DIAGNOSTIC RESULTS)
1. Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to “How to Set Diagnostic Test Mode II
(Self-diagnostic Results)”.
2. 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.
3. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
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 “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.
OBD System Operation Chart
Relationship Between MI, 1st Trip DTC, DTC and Detectable Items
When a malfunction is detected for the first time, the 1st trip DTC and the 1st trip freeze frame data are
stored in the ECM memory.
When the same malfunction is detected in two consecutive trips, the DTC and the freeze frame data are
stored in the ECM memory, and the MI will come on.
The MI will go off after the vehicle is driven 3 times (pattern B) with no malfunction. The drive is counted only
when the recorded driving pattern is met (as stored in the ECM). If another malfunction occurs while count-
ing, the counter will reset.
The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (pattern A) without the
same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injection
System, the DTC and freeze frame data will be stored until the vehicle is driven 80 times (pattern C) without
PBIB0092E
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-103
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
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the same malfunction recurring. The “TIME” in “SELF-DIAGNOSTIC RESULTS” mode of CONSULT-III will
count the number of times the vehicle is driven.
The 1st trip DTC is not displayed when the self-diagnosis results in OK for the 2nd trip.
Summary Chart
For details about patterns B and C under “Fuel Injection System” and “Misfire”, see “EXPLANATION FOR DRIVING PATTERNS FOR
“MISFIRE
For details about patterns A and B under Other, see “EXPLANATION FOR DRIVING PATTERNS FOR “MISFIRE
*1: Clear timing is at the moment OK is detected.
*2: Clear timing is when the same malfunction is detected in the 2nd trip.
Relationship Between MI, DTC, 1st Trip DTC and Driving Patterns for “Misfire
el Injection System”
Items Fuel Injection System Misfire Other
MI (goes off) 3 (pattern B)3 (pattern B) 3 (pattern B)
DTC, Freeze Frame Data (no
display)80 (pattern C) 80 (pattern C) 40 (pattern A)
1st Trip DTC (clear)
1 (pattern C), *
11 (pattern C), *11 (pattern B)
1st Trip Freeze Frame Data
(clear)*1, *2 *1, *2 1 (pattern B)
EC-104
< FUNCTION DIAGNOSIS >[HR16DE (WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
Explanation for Driving Patterns for “Misfire
Driving pattern B means the vehicle operation as follows:
All components and systems should be monitored at least once by the OBD system.
*1: When the same malfunction is de-
tected in two consecutive trips, MI will
light up.*2: MI will go off after vehicle is driven 3
times (pattern B) without any mal-
functions.*3: When the same malfunction is de-
tected in two consecutive trips, the
DTC and the freeze frame data will be
stored in ECM.
*4: The DTC and the freeze frame data
will not be displayed any longer after
vehicle is driven 80 times (pattern C)
without the same malfunction. (The
DTC and the freeze frame data still
remain in ECM.)*5: When a malfunction is detected for
the first time, the 1st trip DTC and the
1st trip freeze frame data will be
stored in ECM.*6: The 1st trip DTC and the 1st trip
freeze frame data will be cleared at
the moment OK is detected.
*7: When the same malfunction is de-
tected in the 2nd trip, the 1st trip
freeze frame data will be cleared.*8: 1st trip DTC will be cleared when ve-
hicle is driven once (pattern C) with-
out the same malfunction after DTC
is stored in ECM.
SEF392S