2014 NISSAN TEANA ECU

EC-68
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DIAGNOSIS SYSTEM (ECM)
Only one set of freeze frame data (either 1st trip freez
e frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM me mory 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/MIL 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 saved 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 fr eeze frame data is stored in the ECM memory and freeze
frame data with the same priority occurs later, t he first (original) freeze frame data remains unchanged in the
ECM memory.
Both 1st trip freeze frame data and freeze frame dat a (along with the DTCs) are cleared when the ECM mem-
ory is erased.
DIAGNOSIS DESCRIPTION : Counter SystemINFOID:0000000009462114
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.
• The MIL will turn 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
C) without the same malfunction recurring. The “TIM E” in “SELF-DIAGNOSTIC RESULTS” mode of CON-
SULT 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.
COUNTER SYSTEM CHART
For details about patterns B and C under “Fuel Inject ion System” and “Misfire”, see “EXPLANATION FOR
DRIVING PATTERNS FOR “MISFIRE ”, “FUEL INJECTION SYS-
TEM”.
For details about patterns A and B under Other, s ee “EXPLANATION FOR DRIVING PATTERNS FOR “MIS-
FIRE ”, “FUEL INJECTION SYSTEM”.
• *1: Clear timing is at the moment OK is detected.
• *2: Clear timing is when the same ma lfunction is detected in the 2nd trip.
Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns for “Misfire terioration>”, “Fuel Injection System”
Priority Items
1 Freeze frame data Misfire — DTC: P0300 – P0304
Fuel Injection System Function — DTC: P0171, P0172
2 Except the above items
3 1st trip freeze frame data
Items Fuel Injection System Misfire Other
MIL (turns OFF) 3 (pattern B) 3 (pattern B) 3 (pattern B)
DTC, Freeze Frame Data (no display) 80 (p attern C) 80 (pattern 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)
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DIAGNOSIS SYSTEM (ECM)EC-69
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Explanation for Driving Patterns for “Misfire st Quality Deterioration>”, “Fuel Injection System”
Driving Pattern B
Refer to EC-71, "DIAGNOSIS DESCRIPTION : Driving Pattern".
*1: When the same malfunction is de-
tected in two consecutive trips, MIL
will light up. *2: MIL will turn OFF after vehicle is driv-
en 3 times (pattern B) without any
malfunctions. *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.
JMBIA1417GB
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DIAGNOSIS SYSTEM (ECM)EC-71
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Explanation for Driving Patterns Except for “Misfire ”, “Fuel Injection
System”
Driving Pattern A
Refer to EC-71, "DIAGNOSIS DESCRIPTION : Driving Pattern".
Driving Pattern B
Refer to EC-71, "DIAGNOSIS DESCRIPTION : Driving Pattern".
DIAGNOSIS DESCRIPTION : Driving PatternINFOID:0000000009462115
CAUTION:
Always drive at a safe speed.
DRIVING PATTERN A
Driving pattern A means a trip satisfying the following conditions.
• Engine speed reaches 400 rpm or more.
• Engine coolant temperature rises by 20 °C (36 °F) or more after starting the engine.
• Engine coolant temperature reaches 70 °C (158 °F) or more.
• The ignition switch is turned from ON to OFF.
NOTE:
• When the same malfunction is detected regardless of driv ing conditions, reset the counter of driving pattern
A.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern A.
DRIVING PATTERN B
Driving pattern B means a trip satisfying the following conditions.
• Engine speed reaches 400 rpm or more.
• Engine coolant temperature reaches 70 °C (158 °F) or more.
• Vehicle speed of 70 – 120 km/h (44 – 75 MPH) is maintained for 60 seconds or more under the control of closed loop.
• Vehicle speed of 30 – 60 km/h (19 – 37 MPH) is maintained for 10 seconds or more under the control of closed loop.
• Under the closed loop control condition, the following state reaches 12 seconds or more in total: Vehicle
speed of 4 km/h (2 MPH) or less with idling condition.
• The state of driving at 10 km/h (7 MPH) or more reaches 10 minutes or more in total.
• A lapse of 22 minutes or more after engine start.
NOTE:
• Drive the vehicle at a constant velocity.
• When the same malfunction is detected regardless of driv ing conditions, reset the counter of driving pattern
B.
• When the above conditions are satisfied without detecting t he same malfunction, reset the counter of driving
pattern B.
DRIVING PATTERN C
Driving pattern C means operating vehicle as per the following:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data) ±375 rpm
*1: When the same malfunction is de-
tected in two consecutive trips, MIL
will light up. *2: MIL will turn OFF after vehicle is driv-
en 3 times (pattern B) without any
malfunctions. *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.
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DIAGNOSIS SYSTEM (ECM)EC-73
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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.
When all SRT related self-diagnoses show OK results in a single cycle (Ignition OFF-ON-OFF), the SRT will
indicate “CMPLT”. → Case 1 above
When all SRT related self-diagnoses show OK results through several different cycles, the SRT will indicate
“CMPLT” at the time the respective se lf-diagnoses have at least one OK result. → Case 2 above
If one or more SRT related self-diagnoses show NG resu lts in 2 consecutive cycles, the SRT will also indicate
“CMPLT”. → Case 3 above
The table above shows that the minimum number of cycles for setting SRT as “INCMP” is the number one (1)
for each self-diagnosis (Case 1 & 2) or the number two (2) for one of self-diagnoses (Case 3). However, in
preparation for the state emissions inspection, it is unnecessary for each self-diagnosis to be executed twice
(Case 3) for the following reasons:
• The SRT will indicate “CMPLT” at the time the respective self-diagnoses have one (1) OK result.
• The emissions inspection requires “CMPLT” of the SRT only with OK self-diagnosis results.
• During SRT driving pattern, the 1st trip DTC (NG) is detected prior to “CMPLT” of SRT and the self-diagnosis
memory must be erased from the ECM after repair.
• If the 1st trip DTC is erased, all the SRT will indicate “INCMP”. NOTE:
SRT can be set as “CMPLT” together with the DTC(s) . Therefore, DTC check must always be carried out
prior to the state emission inspection even though the SRT indicates “CMPLT”.
DIAGNOSIS DESCRIPTION : Permanent Di agnostic Trouble Code (Permanent DTC)
INFOID:0000000009462117
Permanent DTC is defined in SAE J1979/ISO 15031-5 Service $0A.
ECM stores a DTC issuing a command of turning on MIL as a permanent DTC and keeps storing the DTC as
a permanent DTC until ECM judges that there is no presence of malfunction.
Permanent DTCs cannot be erased by using the erase f unction of CONSULT or Generic Scan Tool (GST) and
by disconnecting the battery to shut off power to ECM. This prevents a vehicle from passing the in-use inspec-
tion without repairing a malfunctioning part.
When not passing the in-use inspection due to more than one permanent DTC, permanent DTCs should be
erased, referring to this manual.
NOTE:
• The important items in in-use inspection are that MIL is not ON, SRT test items are set, and permanent
DTCs are not included.
• Permanent DTCs do not apply for regions that permanent DTCs are not regulated by law.
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”
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EC-74
< SYSTEM DESCRIPTION >[QR25DE]
DIAGNOSIS SYSTEM (ECM)
PERMANENT DTC SET TIMING
The setting timing of permanent DTC is stored in EC
M with the lighting of MIL when a DTC is confirmed.
DIAGNOSIS DESCRIPTION : Malfunction Indicator Lamp (MIL)INFOID:0000000009462118
When emission-related ECU detects a malfunction in the emission
control systems components and/or the powertrain control compo-
nents (which affect vehicle emissions), it turns on/blinks MIL to
inform the driver that a malfunction has been detected.
1. The MIL illuminates when ignition switch is turned ON (engine is not running).
NOTE:
Check the MIL circuit if MIL does not illuminate. Refer to EC-
517, "Diagnosis Procedure".
2. When the engine is started, the MIL should go off.
NOTE:
If MIL continues to illuminate/blink, perform self-diagnoses and
inspect/repair accordingly because an emission-rela ted ECU has detected a malfunction in the emission
control systems components and/or the powertrain cont rol components (which affect vehicle emissions).
On Board Diagnosis FunctionINFOID:0000000009462119
ON BOARD DIAGNOSIS ITEM
The on board diagnostic system has the following functions.
BULB CHECK MODE
Description
This function allows damage inspection in the MIL bulb (blown, open circuit, etc.).
Operation Procedure
1. Turn ignition switch ON.
2. The MIL on the instrument panel should stay ON. If it remains OFF, check MIL circuit. Refer to EC-517, "Diagnosis Procedure"
.
SRT STATUS MODE
Description
This function allows to read if ECM has completed t he self-diagnoses of major emission control systems and
components. For SRT, refer to EC-72, "DIAGNOSIS DESCRIPTION : System Readiness Test (SRT) Code"
.
Operation Procedure
1. Turn ignition switch ON and wait 20 seconds.
2. SRT status is indicated as shown blow. • ECM continues to illuminate MIL if all SRT codes are set.
JSBIA1315ZZ
Diagnostic test mode Function
Bulb check MIL can be checked.
SRT status ECM can read if SRT codes are set.
Malfunction warning If ECM detects a malfunction, it illuminates or blinks MIL to inform the driver that a malfunction has been detected.
Self-diagnostic results DTCs or 1st trip DTCs stored in ECM can be read.
Accelerator pedal released po-
sition learning ECM can learn the accelerator pedal released position. Refer to
EC-177, "Work Procedure"
.
Throttle valve closed position
learning ECM can learn the throttle valve closed position. Refer to
EC-178, "Work Procedure"
.
Idle air volume learning ECM can learn the idle air volume. Refer to EC-179, "Work Procedure"
.
Mixture ratio self -learning value
clear Mixture ratio self-learning value can be erased. Refer to
EC-181, "Work Procedure"
.
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DIAGNOSIS SYSTEM (ECM)EC-75
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• ECM blinks MIL for about 10 seconds if all SRT codes are not set.
MALFUNCTION WARNING MODE
Description
In this function ECM turns on or blinks MIL when it detects a malfunction in the emission control system com-
ponents and/or the powertrain control components (which affe ct vehicle emissions) to inform the driver that a
malfunction has been detected.
Operation Procedure
1. Turn ignition switch ON.
2. Check that MIL illuminates. If it remains OFF, check MIL circuit. Refer to EC-517, "Diagnosis Procedure"
.
3. Start engine and let it idle. • For two trip detection logic diagnoses, ECM turns on MIL when it detects the same malfunction twice in
the two consecutive driving cycles.
• For 1st trip detection logic diagnoses, ECM turns on MIL when it detects a malfunction in one driving cycle.
• ECM blinks MIL when it detects a malfunction t hat may damage the three way catalyst (misfire).
SELF-DIAGNOSTIC RESULTS MODE
Description
This function allows to indicate DTCs or 1st trip DTCs stored in ECM according to the number of times MIL is
blinking.
How to Set Self-diagnostic Results 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 mal-
function.
• After ignition switch is turned off, ECM is a lways released from the “self-diagnostic results” mode.
1. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
2. Repeat the following procedure quick ly 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 depressed for approx. 10 seconds until the
MIL starts blinking.
NOTE:
Do not release the accelerator pedal for 10 seconds if MIL starts blinking during this period. This blinking
is displaying SRT status and is continued for another 10 seconds.
4. Fully release the accelerator pedal. ECM has entered to “Self-diagnostic results” mode.
JMBIA1515GB
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DIAGNOSIS SYSTEM (ECM)EC-77
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In this way, all the detected malfunctions are classi
fied by their DTC numbers. The DTC 0000 refers to no mal-
function. Refer to EC-105, "DTC Index"
.
How to Erase Self-diagnostic Results
By performing this procedure, ECM memory is erased and the following diagnostic information is erased as
well.
• Diagnostic trouble codes
• 1st trip diagnostic trouble codes
• Freeze frame data
• 1st trip freeze frame data
• System readiness test (SRT) codes
• Test values
NOTE:
Also, if a battery terminal is disconnected, ECM memory is erased and the diagnostic information as listed
above is erased. (The amount of time required for eras ing may vary from a few seconds to several hours.)
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON.
5. Set ECM in “self-diagnostic results” mode.
6. The diagnostic information has been erased from the backup memory in the ECM. Fully depress the accelerator pedal and keep it depressed for more than 10 seconds.
7. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
CONSULT FunctionINFOID:0000000009462120
FUNCTION
*: The following emission-related diagnostic information is 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
SELF-DIAGNOSTIC RESULT MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-105, "DTC Index".)
How to Read DTC and 1st Trip DTC
DTCs and 1st trip DTCs related to the malfunction are displayed in “self-diag results”.
• When ECM detects a 1st trip DTC, 1t” is displayed for “TIME”.
• When ECM has detected a current DTC, “0” is displayed for “TIME”.
• If “TIME” is neither “0” nor “1t”, the DTC occurred in the past and ECM shows the number of times the vehi-
cle has been driven since the last detection of the DTC.
Diagnostic test mode Function
Self Diagnostic Result Self-diagnostic results such as 1st trip DTC, DTC and 1st trip freeze frame data or freeze frame data
can be read and erased quickly.*
Data Monitor Input/Output data in the ECM can be read.
Work support This mode enables a technician to adjust some devices faster and more accurately by following the in-
dications on the CONSULT screen.
Active Test Diagnostic Test Mode in which CONSULT drives some actuators apart from the ECMs and also shifts
some parameters in a specified range.
ECU Identification ECM part number can be read.
DTC Work Support The status of system monitoring tests and the self-diagnosis status/results can be confirmed.
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DIAGNOSIS SYSTEM (ECM)EC-79
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OMonitored item Unit Monitor Item
Selection
Description Remarks
ECU
IN-
PUT
SIG-
NALS MAIN
SIG-NAL
S
ENG SPEED rpm ×ו Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS) and camshaft position sen-
sor (PHASE). • Accuracy becomes poor if en-
gine speed drops below the
idle rpm.
• If the signal is interrupted while
the engine is running, an ab-
normal value may be indicat-
ed.
MAS A/F SE-B1 V ×ו The signal voltage of the mass air flow
sensor is displayed. • When the engine is stopped, a
certain value is indicated.
• When engine is running, spec- ification range is indicated in
“SPEC”.
B/FUEL SCHDL ms ×ו “Base fuel schedule” indicates the fuel in-
jection pulse width programmed into
ECM, prior to any learned on board cor-
rection. • When engine is running, spec-
ification range is indicated in
“SPEC”.
A/F ALPHA-B1 % • The mean value of the air-fuel ratio feed-
back correction factor per cycle is indicat-
ed. • When the engine is stopped, a
certain value is indicated.
• When engine is running, spec-
ification range is indicated in
“SPEC”.
• This data also includes the
data for the air-fuel ratio learn-
ing control.
COOLAN TEMP/S °C or °F ×× • The engine coolant temperature (deter-
mined by the signal voltage of the engine
coolant temperature sensor) is dis-
played. • When the engine coolant tem-
perature sensor is open or
short-circuited, ECM enters
fail-safe mode. The engine
coolant temperature deter-
mined by the ECM is dis-
played.
A/F SEN1 (B1) V ×ו The A/F signal computed from the input
signal of the air fuel ratio (A/F) sensor 1
is displayed.
HO2S2 (B1) V ×ו The signal voltage of the heated oxygen
sensor 2 is displayed.
HO2S2 MNTR(B1) RICH/LEAN ו Display of heated oxygen sensor 2 sig-
nal.
- RICH: means the amount of oxygen after
three way catalyst is relatively small.
- LEAN: means the amount of oxygen after three way catalyst is relatively large. • When the engine is stopped, a
certain value is indicated.
VHCL SPEED SE km/h or mph ×ו The vehicle speed computed from the
vehicle speed signal sent from combina-
tion meter is displayed.
BATTERY VOLT V • The power supply voltage of ECM is dis-
played.
ACCEL SEN 1
V• The accelerator pedal position sensor
signal voltage is displayed. • ACCEL SEN 2 signal is con-
verted by ECM internally.
Thus, it differs from ECM ter-
minal voltage signal.
ACCEL SEN 2
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