2009 NISSAN LATIO ECU

Emission-
related Diagnostic Information " .
HOW TO SWITCH DIAGNOSTIC TEST MODE
NOTE:
• It is better to count the ti me accurately with a clock.
• It is impossible to switch the di agnostic 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 releas ed, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quickly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
3. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 10 seconds until the MIL starts blinking.
4. Fully release the accelerator pedal. 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 de-
tected twice in two consecutive driving cycles (two trip de-
tection 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 an
d 1st trip DTCs to be read.

EC-1072< SERVICE INFOMATION >
[MR TYPE 2]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
tified codes can be identified by using the CONSULT-II I 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 numer als 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 occu rs at an interval of 1.8-second OFF.
In this way, all the detected malfunctions are classi fied by their DTC numbers. The DTC 0000 refers to no mal-
function. (See EC-1015 )
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 memo ry before starting trouble diagnoses.
OBD System Operation Chart INFOID:0000000004499928
RELATIONSHIP BETWEEN MIL, 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 consec utive trips, the DTC and the freeze frame data are
stored in the ECM memory, and the MIL will come on. For details, refer to EC-1051, " Two Trip Detection
Logic " .
• The MIL will go off after the vehicle is driven 3 time s (driving 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 counting, the counter will reset.
• The DTC and the freeze frame data will be stored until the vehicle is driven 40 times (driving pattern A) with-
out the same malfunction recurring (except for Misfire and Fuel Injection System). For Misfire and Fuel Injec-
tion System, the DTC and freez e frame data will be stored until the vehicle is driven 80 times (driving pattern PBIB3005E

EC
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C) without the same malfunction recurring. The “TIM
E” in “SELF-DIAGNOSTIC RESULTS” mode of CON-
SULT-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 ”, “FUEL INJECTION SYSTEM”".
For details about patterns A and B under “Other”, see "EXPLA NATION FOR DRIVING PATTERNS FOR “MISFIRE ITY DETERIORATION>”, “FUEL INJECTION SYSTEM”".
*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 MIL, DTC, 1ST TR IP DTC AND DRIVING PATTERNS FOR “MISFIRE
”, “FUEL INJECTION SYSTEM”
Items Fuel Injection System Misfire Other
MIL (goes off) 3 (pattern B) 3 (pattern B) 3 (pattern B)
DTC, Freeze Frame Data (no
display) 80 (pattern C) 80 (pa
ttern C) 40 (pattern A)
1st Trip DTC (clear) 1 (pattern C), *1 1 (pattern C), *1 1 (pattern B)
1st Trip Freeze Frame Data
(clear) *1, *2 *1, *2 1 (pattern B)

EC-1074< SERVICE INFOMATION >
[MR TYPE 2]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EXPLANATION FOR DRIVING PATTERNS FOR “M ISFIRE TION>”, “FUEL INJECTION SYSTEM”

Driving pattern B means the vehicle operation as follows: *1: When the same malfunction is de-
tected in two consecutive trips, MIL
will light up. *2: MIL 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

EC-1076< SERVICE INFOMATION >
[MR TYPE 2]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EXPLANATION FOR DRIVING PATTERNS EXCEPT FOR “MISFIRE RIORATION>”, “FUEL INJECTION SYSTEM” *1: When the same malfunction is de-
tected in two consecutive trips, MIL
will light up. *2: MIL 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 40 times (pattern A)
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: 1st trip DTC will
be cleared after vehi-
cle is driven once (pattern B) without
the same malfunction.
*7: When the same malfunction is de- tected in the 2nd trip, the 1st trip
freeze frame data will be cleared. SEF393SD

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*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item Regarding items of DTC and 1st trip DTC, refer to EC-1052, " Emission-related Diagnostic Information " .
Freeze Frame Data and 1st Trip Freeze Frame Data EVAP SYSTEM CLOSE CLOSE THE EVAP CANISTER VENT CONTROL VALVE IN
ORDER TO MAKE EVAP SYSTEM CLOSE UNDER THE
FOLLOWING CONDITIONS.
• IGN SW “ON”
• ENGINE NOT RUNNING
• AMBIENT TEMPERATURE IS ABOVE 0 °C (32 °F).
• NO VACUUM AND NO HIGH PRESSURE IN EVAP SYS- TEM
• FUEL TANK TEMP. IS MORE THAN 0 °C (32 °F).
• WITHIN 10 MINUTES AFTER STARTING “EVAP SYS- TEM CLOSE”
• WHEN TRYING TO EXECUTE “EVAP SYSTEM CLOSE” UNDER THE CONDITION EXCEPT ABOVE, CONSULT-
III WILL DISCONTINUE IT AND DISPLAY APPROPRI-
ATE INSTRUCTION.
NOTE:
WHEN STARTING ENGINE, CONSULT-III MAY DIS-
PLAY “BATTERY VOLTAGE IS LOW. CHARGE BAT-
TERY”, EVEN IN USING CHARGED BATTERY. When detecting EVAP vapor leak
point of EVAP system
TARGET IDLE RPM ADJ* • IDLE CONDITION When setting target idle speed
TARGET IGN TIM ADJ* • IDLE CONDITION Wh en adjusting target ignition tim-
ing
VIN REGISTRATION • IN THIS MODE, VIN IS REGISTERED IN ECM. When registering VIN in ECM WORK ITEM CONDITION USAGE )
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
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.
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 schedule.
ENGINE SPEED [rpm] • The engine sp eed at the moment a malfunction is de tected is displayed.
VEHICL SPEED
[km/h] or [mph] • The vehicle speed at the moment a malfunction is detected is displayed.
ABSOL TH-P/S [%] • The throttle valve opening angle at the moment a malfunction is detected is displayed.
B/FUEL SCHDL [msec] • The ba se fuel schedule at the moment a malfunctio n is detected is displayed.
INT/A TEMP SE
[ ° C] or [ °F] • The intake air temperature at the moment a malfunction is detected is displayed.

Emission-related Diagnostic Information " .
>> GO TO 2. Ground Inspection " .
OK or NG OK >> GO TO 3.
NG >> Repair or replace. How to Perform Efficient Diagnosis for an Electrical Incident " , “INCIDENT SIMULATION
TESTS”.
OK or NG OK >> GO TO 4.
NG >> Repair or replace. How to Check Terminal " , “HOW TO PROBE CONNECTORS”, “How to Check Enlarged Con-
tact Spring of Terminal”.
OK or NG OK >>
INSPECTION END
NG >> Repair or replace connector. STEP in Work Flow Situation
2 The CONSULT-III is used. The SELF-DIAG RESULTS screen shows time data other than 0 or [1t].
3 or 4 The symptom described by the customer does not recur. 5 (1st trip) DTC does not appear during the DTC Confirmation Procedure.
10 The Diagnostic Procedure for PXXXX does not indicate the malfunctioning area.

EC-1144< SERVICE INFOMATION >
[MR TYPE 2]
POWER SUPPLY AND GROUND CIRCUIT
Ground Inspection INFOID:0000000004499957
Ground connections are very important to the proper oper ation of electrical and electronic circuits. Ground
connections are often exposed to moisture, dirt and ot her corrosive elements. The corrosion (rust) can
become an unwanted resistance. This unwanted resistance can change the way a circuit works.
Electronically controlled circuits are very sensitive to proper grounding. A loose or corroded ground can drasti-
cally affect an electronically controlled circuit. A poor or corroded ground can easily affect the circuit. Even
when the ground connection looks clean, there can be a thin film of rust on the surface.
When inspecting a ground connection follow these rules:
• Remove the ground bolt or screw.
• Inspect all mating surfaces for tarnish, dirt, rust, etc.
• Clean as required to assure good contact.
• Reinstall bolt or screw securely.
• Inspect for “add-on” accessories which may be interfering with the ground circuit.
• If several wires are crimped into one ground eyelet termi nal, check for proper crimps. Make sure all of the
wires are clean, securely fastened and providing a good ground path. If multiple wires are cased in one eye-
let make sure no ground wires have excess wire insulation.
For detailed ground distribution information, refer to PG-29, " Ground Distribution " .
PBIB1870E