2009 NISSAN LATIO air condition

Diagnosis Procedure " .
Sensor Input Signal to ECM
ECM
function Actuator
Camshaft position sensor (PHASE)
Crankshaft position sensor (POS) Engine speed
Air fuel ratio (A/F) sensor 1
heater control Air fuel ratio (A/F) sensor 1 heat-
er
Mass air flow sensor Amount of intake air MONITOR ITEM CONDITION SPECIFICATION
A/F S1 HTR (B1) • Engine: After warming up, idle the engine
(More than 140 seconds after starting engine.) 4 - 100%DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0031
0031 Air fuel ratio (A/F)
sensor 1 heater
control circuit low The current amperage in th
e air fuel ratio (A/F)
sensor 1 heater circuit is out of the normal range.
[An excessively low voltage signal is sent to ECM
through the air fuel ratio (A/F) sensor 1 heater.] • Harness or connectors
[Air fuel ratio (A/F) sensor 1 heater circuit is
open or shorted.]
• Air fuel ratio (A/F) sensor 1 heater
P0032
0032 Air fuel ratio (A/F)
sensor 1 heater
control circuit high The current amperage in th
e air fuel ratio (A/F)
sensor 1 heater circuit is out of the normal range.
[An excessively high voltage signal is sent to ECM
through the air fuel ratio (A/F) sensor 1 heater.] • Harness or connectors
[Air fuel ratio (A/F) sensor 1 heater circuit is
shorted.]
• Air fuel ratio (A/F) sensor 1 heater

EC-642< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0031, P0032
A/F SENSOR 1 HEATER
Do not use ECM ground terminals when measuring in put/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground ot her than ECM terminals, such as the ground.
: Average voltage for pulse signal (Actual pulse signal can be confirmed by oscilloscope.)
Diagnosis Procedure INFOID:00000000045370931.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body. Refer to EC-632, " Ground Inspection " .
OK or NG OK >> GO TO 2.
NG >> Repair or replace ground connections. 2.
CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT
1. Disconnect air fuel ratio (A/F) sensor 1 harness connector (1).
2. Turn ignition switch ON.
- Air fuel ratio (A/F) sensor 1 (2) TERMI-
NAL
NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
3 G A/F sensor 1 heater [Engine is running]
• Warm-up condition
• Idle speed
(More than 140 seconds after starting
engine) Approximately 2.9 - 8.8V
49 W A/F sensor 1 [Engine is running]
• Warm-up condition
• Engine speed: 2,000 rpm Approximately 1.8V
Output voltage varies with air fuel
ratio.
53 B A/F sensor 1 [Ignition switch: ON]Approximately 2.2V PBIA8148J
:
Vehicle front
1. Body ground E24 2. Engine ground F9 3. Engine ground F16
4. Body ground E15 BBIA0698E
BBIA0699E

EC
NP
O
DTC P0037, P0038 HO2S2 HEATER
Description INFOID:0000000004537096
SYSTEM DESCRIPTION
The ECM performs ON/OFF control of the heated oxygen sensor 2 heater corresponding to the engine speed,
amount of intake air and engine coolant temperature.
OPERATION
CONSULT-III Reference Val ue in Data Monitor Mode INFOID:0000000004537097
Specification data are reference values.
On Board Diagnosis Logic INFOID:0000000004537098
DTC Confirmation Procedure INFOID:0000000004537099
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confi rm that battery voltage is between 10.5V and 16V at
idle.
1. Start engine and warm it up to the normal operating temperature. Sensor Input Signal to ECM ECM Function Actuator
Camshaft position sensor (PHASE) Engine speed
Heated oxygen sensor 2
heater control Heated oxygen sensor 2 heater
Crankshaft position sensor (POS)
Engine coolant temperature sensor Engine coolant tempera-
ture
Mass air flow sensor Amount of intake air Engine speed rpm Heated oxygen sensor 2 heater
Above 3,600 OFF
• Below 3,600 rpm after the following conditions are met.
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and at idle for 1 minute under no load ONMONITOR ITEM CONDITION SPECIFICATION
HO2S2 HTR (B1) • Engine speed: Below 3,600 rpm after the following conditions are met
- Engine: After warming up
- Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load. ON
• Engine speed: Above 3,600 rpm OFF DTC No.
Trouble diagnosis
name DTC detecting condition Possible cause
P0037
0037 Heated oxygen
sensor 2 heater
control circuit low The current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively low voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) • Harness or connectors
(Heated oxygen sensor 2 heater circuit is
open or shorted.)
• Heated oxygen sensor 2 heater
P0038
0038 Heated oxygen
sensor 2 heater
control circuit high The current amperage in the heated oxygen sensor
2 heater circuit is out of the normal range.
(An excessively high voltage signal is sent to ECM
through the heated oxygen sensor 2 heater.) • Harness or connectors
(Heated oxygen sensor 2 heater circuit is
shorted.)
• Heated oxygen sensor 2 heater

DTC P0101 MAF SENSOR
EC-655
< SERVICE INFOMATION >
[MR TYPE 1] C
D E
F
G H
I
J
K L
M A EC
NP
O
DTC P0101 MAF SENSOR
Component Description INFOID:0000000004537112
The mass air flow sensor (1) is plac ed in the stream of intake air. It
measures the intake flow rate by measuring a part of the entire
intake flow. The mass air flow sens or controls the temperature of the
hot wire to a certain amount. The heat generated by the hot wire is
reduced as the intake air flows around it. The more air, the greater
the heat loss.
Therefore, the electric current supplied to hot wire is changed to
maintain the temperature of the hot wire as air flow increases. The
ECM detects the air flow by means of this current change.
CONSULT-III Reference Val ue in Data Monitor Mode INFOID:0000000004537113
Specification data are reference values.
On Board Diagnosis Logic INFOID:0000000004537114
DTC Confirmation Procedure INFOID:0000000004537115
Perform PROCEDURE FOR MALFUNCTION A first.
If the DTC cannot be confirmed, perform PROCEDURE FOR MALFUNCTION B.
NOTE:
If DTC Confirmation Procedure has been previously conduc ted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test. PBIA9559J
MONITOR ITEM CONDITION SPECIFICATION
MAS A/F SE-B1 • See EC-618 .
CAL/LD VALUE • Engine: After warming up
• Shift lever: P or N (A/T, CVT), Neutral (M/T)
• Air conditioner switch: OFF
• No load Idle 10% - 35%
2,500 rpm 10% - 35%
MASS AIRFLOW • Engine: After warming up
• Shift lever: P or N (A/T, CVT),
Neutral (M/T)
• Air conditioner switch: OFF
• No load Idle 1.0 - 4.0 g·m/s
2,500 rpm 4.0 - 10.0 g·m/s DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0101
0101 Mass air flow sensor cir-
cuit range/performance A)
A high voltage from the sensor is sent to ECM
under light load driving condition. • Harness or connectors
(Mass air flow sensor circuit is
open or shorted.)
• Mass air flow sensor
• EVAP control system pressure
sensor
• Intake air temperature sensor
B) A low voltage from the sensor is sent to ECM un-
der heavy load driving condition. • Harness or connectors
(Mass air flow sensor circuit is
open or shorted.)
• Intake air leaks
• Mass air flow sensor
• EVAP control system pressure sensor
• Intake air temperature sensor

EC-656< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0101 MAF SENSOR
PROCEDURE FOR MALFUNCTION A
NOTE:
If engine will not start or stops soon, wait at leas t 10 seconds with engine stopped (Ignition switch ON) instead
of running engine at idle speed.
1. Start engine and warm it up to normal operating temperature.
2. Run engine for at least 10 seconds at idle speed.
3. Check 1st trip DTC.
4. If 1st trip DTC is detected, go to EC-659, " Diagnosis Procedure " .
PROCEDURE FOR MALFUNCTION B
CAUTION:
Always drive vehicle at a safe speed.
With CONSULT-III
1. Turn ignition switch ON.
2. Start engine and warm it up to normal operating temperature.
If engine cannot be started, go to EC-659, " Diagnosis Procedure " .
3. Select “DATA MONITOR” mode with CONSULT-III.
4. Check the voltage of “MAS A/F SE-B1” with “DATA MONITOR”.
5. Increases engine speed to about 4,000 rpm.
6. Monitor the linear voltage rise in response to engine speed
increases.
If NG, go to EC-659, " Diagnosis Procedure " .
If OK, go to following step.
7. Maintain the following conditions for at least 10 consecutive seconds.
8. Check 1st trip DTC.
9. If 1st trip DTC is detected, go to EC-659, " Diagnosis Procedure " .
Overall Function Check INFOID:0000000004537116
PROCEDURE FOR MALFUNCTION B
Use this procedure to check the overall function of the ma ss air flow sensor circuit. During this check, a 1st
DTC might not be confirmed.
With GST PBIB3457E
ENG SPEED More than 2,000 rpm
THRTL SEN 1 More than 3V
THRTL SEN 2 More than 3V
Shift lever Suitable position
Driving location Driving vehicle uphill (Increased engine load) will help
maintain the driving conditions required for this test.

DTC P0101 MAF SENSOR
EC-659
< SERVICE INFOMATION >
[MR TYPE 1] C
D E
F
G H
I
J
K L
M A EC
NP
O
Diagnosis Procedure
INFOID:00000000045371181.
INSPECTION START
Which malfunction (A or B) is duplicated?
A or B A >> GO TO 3.
B >> GO TO 2. 2.
CHECK INTAKE AIR LEAK
Check the following for connections.
• Air duct
• Vacuum hoses
• Intake air passage between air duct and intake manifold
OK or NG OK >> GO TO 3.
NG >> Reconnect the parts. 3.
CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screw on the body.
Refer to EC-632, " Ground Inspection " .
TER-
MI-
NAL
NO. WIRE
COLOR ITEM CONDITION DATA (DC Voltage)
32 P ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]
• For a few seconds after turning ignition switch
OFF 0 - 1.0V
[Ignition switch: OFF]
• More than a few seconds after turning ignition switch OFF BATTERY VOLTAGE
(11 - 14V)
45 G Mass air flow sensor [Engine is running]
• Warm-up condition
• Idle speed 0.8 - 1.1V
[Engine is running]
• Warm-up condition
• Engine speed: 2,500 rpm 1.4 - 1.7V
52 LG Sensor ground
(Mass air flow sensor) [Engine is running]
• Warm-up condition
• Idle speed Approximately 0V
105 G Power supply for
ECM [Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V) BBIA0698E

EC
NP
O
2. Also check harness for short to ground and short to power.
OK or NG OK >> GO TO 8.
NG >> Repair open circuit or short to ground or short or short to power in harness or connectors. Component Inspection " .
OK or NG OK >> GO TO 9.
NG >> Replace intake air temperature sensor. Component Inspection " .
OK or NG OK >> GO TO 10.
NG >> Replace EVAP control system pressure sensor. Component Inspection " .
OK or NG OK >> GO TO 11.
NG >> Replace mass air flow sensor. .
>> INSPECTION END
Component Inspection INFOID:0000000004537119
MASS AIR FLOW SENSOR With CONSULT-III
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Connect CONSULT-III and select “DATA MONITOR” mode.
4. Select “MAS A/F SE-B1” and check i ndication under the following conditions.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
5. If the voltage is out of spec ification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following. • Crushed air ducts
• Malfunctioning seal of air cleaner element
• Uneven dirt of air cleaner element
• Improper specification of intake air system parts Continuity should exist.

EC-662< SERVICE INFOMATION >
[MR TYPE 1]
DTC P0101 MAF SENSOR
b. If NG, repair or replace malfunc tioning part and perform step 2 to 4 again.
If OK, go to next step.
6. Turn ignition switch OFF.
7. Disconnect mass air flow sensor harness connector and reconnect it again.
8. Perform step 2 to 4 again.
9. If NG, clean or replace mass air flow sensor.
Without CONSULT-III
1. Reconnect all harness connectors disconnected.
2. Start engine and warm it up to normal operating temperature.
3. Check voltage between ECM terminal 45 (Mass air flow sensor signal) and ground.
*: Check for linear voltage rise in response to engine being increased to about 4,000 rpm.
4. If the voltage is out of spec ification, proceed the following.
a. Check for the cause of uneven air flow through mass air flow sensor. Refer to following. • Crushed air ducts
• Malfunctioning seal of air cleaner element
• Uneven dirt of air cleaner element
• Improper specification of intake air system parts
b. If NG, repair or replace malfunc tioning part and perform step 2 and 3 again.
If OK, go to next step.
5. Turn ignition switch OFF.
6. Disconnect mass air flow sensor harness connector and reconnect it again.
7. Perform step 2 and 3 again.
8. If NG, clean or replace mass air flow sensor.
Removal and Installation INFOID:0000000004537120
MASS AIR FLOW SENSOR
Refer to EM-139 .Condition Voltage V
Ignition switch ON (Engine stopped.) Approx 0.4
Idle (Engine is warmed-up to normal
operating temperature.) 0.8 - 1.1
2,500 rpm (Engine is warmed-up to
normal operating temperature.) 1.4 - 1.7
Idle to about 4,000 rpm 0.8 - 1.1 to 2.4* PBIA9564J