2009 NISSAN LATIO ECU

PRECAUTIONS
EC-1021
< SERVICE INFOMATION >
[MR TYPE 2] C
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PRECAUTIONS
Precaution for Supplemental Restraint System (SRS) "AIR BAG" and "SEAT BELT
PRE-TENSIONER" INFOID:0000000004499899
The Supplemental Restraint System such as “A IR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severi ty of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and w hether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the “SUPPLEMENTAL RESTRAINT SYS-
TEM” and “SEAT BELTS” of this Service Manual.
WARNING:
• To avoid rendering the SRS inoper ative, which could increase the risk of personal injury or death in
the event of a collision which would result in air bag inflation, all maintenance must be performed by
an authorized NISSAN/INFINITI dealer.
• Improper maintenance, including in correct removal and installation of the SRS, can lead to personal
injury caused by unintentional act ivation of the system. For removal of Spiral Cable and Air Bag
Module, see the “SUPPLEMEN TAL RESTRAINT SYSTEM”.
• Do not use electrical test equipm ent on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identi fied by yellow and/or orange harnesses or har-
ness connectors.
PRECAUTIONS WHEN USING POWER TOOLS (AIR OR ELECTRIC) AND HAMMERS WARNING:
• When working near the Airbag Diagnosis Sensor Un it or other Airbag System sensors with the igni-
tion ON or engine running, DO NOT use air or el ectric power tools or strike near the sensor(s) with a
hammer. Heavy vibration could activate the sensor( s) and deploy the air bag(s), possibly causing
serious injury.
• When using air or electric power tools or hammers , always switch the ignition OFF, disconnect the
battery, and wait at least 3 minutes before performing any service.
Precaution for Procedur e without Cowl Top Cover INFOID:0000000004499900
When performing the procedure after removing cowl top cover, cover
the lower end of windshield with urethane, etc.
On Board Diagnosis (OBD) Syst em of Engine and A/T, CVT INFOID:0000000004499901
The ECM has an on board diagnostic system . It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition sw itch OFF and disconnect the battery ground cable before any repair or
inspection work. The open/short circuit of relate d switches, sensors, solenoid valves, etc. will cause
the MIL to light up.
• Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to the open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Certain systems and components, especially those related to OBD, may use a new style slide-lock-
ing type harness connector. For descripti on and how to disconnect, refer to PG-64 .
• Be sure to route and secure the harnesses properly after work. The interference of the harness with
a bracket, etc. may cause the MIL to li ght up due to the short circuit. PIIB3706J

EC-1022< SERVICE INFOMATION >
[MR TYPE 2]
PRECAUTIONS
• Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to the malfunction of the fuel injection system, etc.
• Be sure to erase the unnecessary malfunction info rmation (repairs completed) from the ECM and
TCM (Transmission control module) before returning the vehicle to the customer.
Precaution INFOID:0000000004499902
• Always use a 12 volt battery as power source.
• Do not attempt to disconnect battery cables while engine is
running.
• Before connecting or disconnecting the ECM harness con-
nector, turn ignition switch OFF and disconnect negative bat-
tery cable. Failure to do so may damage the ECM because
battery voltage is applied to ECM even if ignition switch is
turned OFF.
• Before removing parts, turn ig nition switch OFF and then dis-
connect negative battery cable.
• Do not disassemble ECM.
• If battery cable is disconnected, the memory will return to the
initial ECM values.
The ECM will now start to self-c ontrol at its initial values.
Engine operation can vary slight ly in this case. However, this
is not an indication of a malf unction. Do not replace parts
because of a slight variation.
• If the battery is disconnected, the following emission-related
diagnostic information will be lost within 24 hours.
- Diagnostic trouble codes
- 1st trip diagnostic trouble codes
- Freeze frame data
- 1st trip freeze frame data
- System readiness test (SRT) codes
- Test values
• When connecting ECM harness connector, fasten (B) it
securely with a lever (1) as far as it will go as shown in the fig-
ure.
- ECM (2)
- Loosen (A)
• When connecting or disconnect ing pin connectors into or
from ECM, take care not to damage pin terminals (bend or
break).
Make sure that there are not any bends or breaks on ECM pin
terminal, when connecting pin connectors.
• Securely connect ECM harness connectors.
A poor connection can cause an extremely high (surge) volt-
age to develop in coil and co ndenser, thus resulting in dam-
age to ICs.
• Keep engine control system harness at least 10 cm (4 in) away
from adjacent harness, to preven t engine control system mal-
functions due to receiving exter nal noise, degraded operation
of ICs, etc. SEF289H
PBIA9222J
PBIB2947E
PBIB0090E

EC-1040< SERVICE INFOMATION >
[MR TYPE 2]
EVAPORATIVE EMISSION SYSTEM
Positive pressure is delivered to the EVAP system through the EVAP
service port. If fuel vapor leak age in the EVAP system occurs, use a
leak detector to locate the leak.
Removal and Installation INFOID:0000000004499916
EVAP CANISTER
Tighten EVAP canister as shown in the figure.
EVAP CANISTER VENT CONTROL VALVE
1. Turn EVAP canister vent control valve counterclockwise.
• Lock (A)
• Unlock (B)
2. Remove the EVAP canister vent control valve.
Always replace O-ring with a new one.
How to Detect Fuel Vapor Leakage INFOID:0000000004499917
CAUTION:
• Never use compressed air or a high pressure pump.
• Do not exceed 4.12 kPa (0.042 kg/cm 2
, 0.6 psi) of pressure in EVAP system.
NOTE:
• Do not start engine.
• Improper installation of EVAP service port adapter to the EVAP service port may cause a leak.
WITH CONSULT-III
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Also attach the pressure pump and hose to the EVAP service port adapter. SEF462UC
PBIB1214E
PBIB3091E

EVAPORATIVE EMISSION SYSTEM
EC-1041
< SERVICE INFOMATION >
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3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE” of “WORK SUPPORT” mode with CONSULT-III.
5. Touch “START”. A bar graph (Pressure indicating display) will appear on the screen.
6. Apply positive pressure to the EVAP system until t he pressure indicator reaches the middle of the bar
graph.
7. Remove EVAP service port adapter and hose with pressure pump.
8. Locate the leak using a leak detector. Refer to EC-1036," Description " .
WITHOUT CONSULT-III
1. Attach the EVAP service port adapter securely to the EVAP ser- vice port.
2. Also attach the pressure pump with pressure gauge to the EVAP service port adapter.
3. Apply battery voltage to the termi nal of EVAP canister vent con-
trol valve (3) to make a closed EVAP system.
• EVAP control system pressure sensor (1)
• EVAP canister (2)
4. To locate the leak, deliver positive pressure to the EVAP system until pressure gauge points reach 1.38 to
2.76 kPa (0.014 to 0.028 kg/cm 2
, 0.2 to 0.4 psi).
5. Remove EVAP service port adapter and hose with pressure pump.
6. Locate the leak using a leak detector. Refer to EC-1036, " Description " . SEF200U
SEF462UC
BBIA0693E

EC-1042< SERVICE INFOMATION >
[MR TYPE 2]
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
ON BOARD REFUELING VAPOR RECOVERY (ORVR)
System Description INFOID:0000000004499918
From the beginning of refueling, the air and vapor insi de the fuel tank go through refueling EVAP vapor cut
valve and EVAP/ORVR line to the EVAP canister. The vapor is absorbed by the EVAP canister and the air is
released to the atmosphere.
When the refueling has reached the full level of the fuel tank, the refueling EVAP vapor cut valve is closed and
refueling is stopped because of auto shut-off. The vapor which was absorbed by the EVAP canister is purged
during driving.
WARNING:
When conducting inspections below, be sure to observe the following:
• Put a “CAUTION: FLAMMABLE” sign in workshop.
• Do not smoke while servicing fuel system. Keep open flames and sparks away from work area.
• Be sure to furnish the workshop with a CO 2
fire extinguisher.
CAUTION:
• Before removing fuel line parts, carry out the following procedures:
- Put drained fuel in an explosion-pr oof container and put lid on securely.
- Release fuel pressure from fuel line. Refer to EC-1086, " Fuel Pressure Check " .
- Disconnect negative battery cable.
• Always replace O-ring when the fu el gauge retainer is removed.
• Do not kink or twist hose and tube when they are installed.
• Do not tighten hose and clamps excessively to avoid damaging hoses.
• After installation, run engine an d check for fuel leaks at connection.
• Do not attempt to top off the fuel tank afte r the fuel pump nozzle shuts off automatically.
Continued refueling may cause fuel overflow, r esulting in fuel spray and possibly a fire.
Diagnosis Procedure INFOID:0000000004499919
SYMPTOM: FUEL ODOR FROM EVAP CANISTER IS STRONG. 1.
CHECK EVAP CANISTER
1. Remove EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
2. Weigh the EVAP canister with EVAP canister vent control valve and EVAP control system pressure sensor
attached.
The weight should be l ess than 1.9 kg (4.2 lb).
OK or NG OK >> GO TO 2.
NG >> GO TO 3. 2.
CHECK IF EVAP CANISTER SATURATED WITH WATER PBIB1387E

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ON BOARD DIAGNOSTIC (OBD) SYSTEM
Introduction INFOID:0000000004499924
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emis sion-related diagnostic information including:
The above information can be checked using procedures listed in the table below. ×: Applicable —: Not applicable
*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode.
(Refer to EC-1094, " Fail-Safe Chart " .)
Two Trip Detection Logic INFOID:0000000004499925
When a malfunction is detected for the first time, 1st tr ip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The “trip” in the “Two Trip Detection Logic” m eans a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic item s will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
When there is an open circuit on MIL circuit, the ECM c annot warn the driver by MIL lighting up when there is
malfunction on engine control system. Emission-related diagnostic information Diagnostic service
Diagnostic Tr ouble Code (DTC) Service $03 of SAE J1979
Freeze Frame data Service $02 of SAE J1979
System Readiness Test (SRT) code Service $01 of SAE J1979
1st Trip Diagnostic Trou ble Code (1st Trip DTC) Service $07 of SAE J1979
1st Trip Freeze Frame data
Test values and Test limi ts Service $06 of SAE J1979
Calibration ID Servic e $09 of SAE J1979
DTC 1st trip DTC Freeze Frame
data 1st trip Freeze
Frame data SRT code SRT status Test value
CONSULT-III × × × × × × —
GST × × × —× × ×
ECM × ×* — — — ×— Items
MIL DTC 1st trip DTC
1st trip 2nd trip 1st trip
displaying 2nd trip
displaying 1st trip
displaying 2nd trip
display-
ing
Blinking Lighting
up Blinking
Lighting
up
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0304 is
being detected ×
— — — — — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0304 is
being detected — —
×— — ×— —
One trip detection diagnoses
(Refer to EC-1052, " Emission-relat-
ed Diagnostic Information " .)
—
×— — ×— — —
Except above — — — ×— × × —

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*1: 1st trip DTC No. is
the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results), this number is controlled by NISSAN.
*4: The troubleshooting for this DTC needs CONSULT-III.
*5: When the ECM in the mode of displaying SRT status, MIL may flash. For the details, refer to "How to Display SRT Status".
*6: SRT code will not be set if the self-diagnostic result is NG.
*7: When the fail-safe operations for both self-diagnoses occur, the MIL illuminates.
*8: When erasing this DTC, al ways use CONSULT-III or GST.
DTC AND 1ST TRIP DTC The 1st trip DTC (whose number is the same as the DT C number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously , and the 1st trip DTC did not recur, 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 MIL will not
light up (two trip detection logic). If the same malfunc tion 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 t he ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL light s 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. Fo r malfunctions that blink or light up the MIL 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 DT C from the ECM memory are described in "HOW TO
ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION".
For malfunctions in which 1st trip DTCs are displa yed, refer to "EMISSION-RELATED DIAGNOSTIC INFOR-
MATION ITEMS". These items are required by legal r egulations to continuously monitor the system/compo-
nent. In addition, the items monitored non-cont inuously are also displayed on CONSULT-III.
1st trip DTC is specified in Service $07 of SAE J1979. 1st trip DTC detection occurs without lighting up the MIL
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-1089, " Trouble Diagnosis Introduction " . Then
perform DTC Confirmation Procedure or Overall Function C heck to try to duplicate the malfunction. If the mal-
function is duplicated, the item requires repair.
How to Read DTC and 1st Trip DTC DTC and 1st trip DTC can be read by the following methods.
WITH CONSULT-III
WITH GST
CONSULT-III or GST (Generic Scan Tool ) Examples: P0340, P0850, P1148, etc.
These DTCs are prescribed by SAE J2012. ETC MOT PWR-B1 P2100 2100 — 1
×EC-1447 ETC FNCTN/CIRC-B1 P2101 2101 — 1
×EC-1451 ETC MOT PWR P2103 2103 — 1
×EC-1447 ETC MOT-B1 P2118 2118 — 1
×EC-1457 ETC ACTR-B1 P2119 2119 — 1
×EC-1462 APP SEN 1/CIRC P2122 2122 — 1
×EC-1464 APP SEN 1/CIRC P2123 2123 — 1
×EC-1464 APP SEN 2/CIRC P2127 2127 — 1
×EC-1469 APP SEN 2/CIRC P2128 2128 — 1
×EC-1469 TP SENSOR-B1 P2135 2135 — 1
×EC-1476 APP SENSOR P2138 2138 — 1
×EC-1481 A/F SENSOR1 (B1) P2A00 2A00 — 2
×EC-1488 Items
(CONSULT-III screen terms) DTC*
1
SRT code Trip MIL lighting up Reference
CONSULT-III
GST* 2
ECM*3

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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.
If, during the state emissions inspection, the SRT indica tes “CMPLT” for all test items, the inspector will con-
tinue with the emissions test. However, if the SRT i ndicates “INCMP” for one or more of the SRT items the
vehicle is returned to the customer untested.
NOTE:
If MIL is ON during the state emissi ons inspection, the vehicle is also returned to the customer untested even
though the SRT indicates “CMPLT” for all test items. T herefore, it is important to check SRT (“CMPLT”) and
DTC (No DTCs) before the inspection.
SRT Item The table below shows required self-diagnostic items to set the SRT to “CMPLT”.
*: If completion of several SRTs is required, perform driving patterns (DTC confirmation procedure), one by one based on the pr iority for
models with CONSULT-III.
SRT Set Timing SRT is set as “CMPLT” after self-diagnosis has been performed one or more times. Completion of SRT is
done regardless of whether the result is OK or NG. T he set timing is different between OK and NG results and
is shown in the table below.
OK: Self-diagnosis is carried out and the result is OK.
NG: Self-diagnosis is carried out and the result is NG.
—: Self-diagnosis is not carried out. SRT item
(CONSULT-III indica- tion) Perfor-
mance
Priority* Required self-diagnostic items to set the SRT to “CMPLT” Corresponding DTC No.
CATALYST 2 Three way catalyst function P0420
EVAP SYSTEM 2 EVAP control system purge flow monitoring P0441
1 EVAP control system P0442
2 EVAP control system P0456
HO2S 2 Air fuel ratio (A/F) sensor 1 P0133 Heated oxygen sensor 2 P0137
Heated oxygen sensor 2 P0138
Heated oxygen sensor 2 P0139 Self-diagnosis result
Example
Diagnosis Ignition cycle
← ON → OFF ← ON → OFF ← ON → OFF ← ON →
All OK Case 1 P0400 OK (1) — (1) OK (2) — (2) P0402 OK (1) — (1) — (1) OK (2)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “CMPLT” “CMPLT” “CMPLT” “CMPLT”
Case 2 P0400 OK (1) — (1) — (1) — (1) P0402 — (0) — (0) OK (1) — (1)
P1402 OK (1) OK (2) — (2) — (2)
SRT of EGR “INCMP” “INCMP” “CMPLT” “CMPLT”
NG exists Case 3 P0400 OK OK — — P0402 — — — —
P1402 NG — NG NG
(Consecutive NG)
(1st trip) DTC 1st trip DTC — 1st trip DTC DTC
(= MIL “ON”)
SRT of EGR “INCMP” “INCMP” “INCMP” “CMPLT”