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OPERATIONEC-49
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OPERATION
AUTMATIC SPEED CONTROL DEVICE (ASCD)
AUTMATIC SPEED CONTROL DEVICE (A
SCD) : Switch Name and Function
INFOID:0 INFINITI QX56 2011 Factory Service Manual
OPERATIONEC-49
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OPERATION
AUTMATIC SPEED CONTROL DEVICE (ASCD)
AUTMATIC SPEED CONTROL DEVICE (A
SCD) : Switch Name and Function
INFOID:0](/manual-img/42/57033/w960_57033-2072.png)
OPERATIONEC-49
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OPERATION
AUTMATIC SPEED CONTROL DEVICE (ASCD)
AUTMATIC SPEED CONTROL DEVICE (A
SCD) : Switch Name and Function
INFOID:0000000006217719
SWITCHES AND INDICATORS
SET SPEED RANGE
ASCD system can be set the following vehicle speed.
SWITCH OPERATION
CANCEL CONDITION
When any of following conditions exist, the cruise operation is canceled.
- CANCEL switch is pressed
- ASCD MAIN switch pressed (Set speed is cleared)
- More than two switches at ASCD steering switch ar e pressed at the same time (Set speed is cleared)
- Brake pedal is depressed
- Selector lever position is changed to N, P or R
- Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
- TCS system is operated
When the ECM detects any of the following conditions , the ECM cancels the cruise operation and informs
the driver by blinking CRUISE indicator lamp.
1. CRUISE indicator lamp 2. CANCEL switch 3. ASCD MAIN switch
4. SET/COAST switch 5. RESUME/ACCELERATE switch
A. On the combination meter B. On the steering wheel
JPBIA3226ZZ
Minimum speed (Approx.) Maximum speed (Approx.)
40 km/h (25 MPH) 143 km/h (88 MPH)
Item Function
CANCEL switch Cancels the cruise control driving.
RESUME/ACCELERATE switch Resumes the set speed.
Increases speed incrementally during cruise control driving.
SET/COAST switch Sets desired cruise speed.
Decreases speed incrementally during cruise control driving.
ASCD MAIN switch Master switch to activate the ASCD system.
(CRUISE indicator lamp is turn
ed ON when ASCD system is ON.)
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OPERATION
- Engine coolant temperature is slightly higher than
the normal operating temperature. Then CRUISE indica-
tor lamp is blinked slowly.
NOTE:
Engine coolant temperature decreases to the norma l operating temperature, CRUISE indicator lamp stop
blinking and the cruise operation is able to work.
- Malfunction for some self-diagnoses regarding ASCD s ystem. CRUISE indicator lamp is blinked quickly.
When ASCD MAIN switch is turned to OFF during the cr uise control driving, all of ASCD operations is can-
celed and vehicle speed memory is erased.
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ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-51
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
Diagnosis DescriptionINFOID:0000000006217720
This system is an on board diagnostic system that re
cords exhaust emission-related diagnostic information
and detects a sensors/actuator-related malfunction. A ma lfunction is indicated by the malfunction indicator
lamp (MIL) and stored in ECU memory as a DTC. The diagnostic information can be obtained with the diag-
nostic tool (GST: Generic Scan Tool).
GST (Generic Scan Tool)INFOID:0000000006217721
When GST is connected with a data link connector equipped on the vehicle side, it will communicate with the
control unit equipped in the vehicle and then enable va rious kinds of diagnostic tests. Refer to GI-48, "
Descrip-
tion".
NOTE:
Service $0A is not applied for r egions where it is not mandated.
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DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1st Trip Detect
ion Logic and Two Trip Detection Logic
INFOID:00000000 INFINITI QX56 2011 Factory Service Manual
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DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1st Trip Detect
ion Logic and Two Trip Detection Logic
INFOID:00000000](/manual-img/42/57033/w960_57033-2075.png)
EC-52
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DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS SYSTEM (ECM)
DIAGNOSIS DESCRIPTION
DIAGNOSIS DESCRIPTION : 1st Trip Detect
ion Logic and Two Trip Detection Logic
INFOID:0000000006217722
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 illuminate 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 illuminates. The MIL illu minates at the same time when the DTC is stored.
<2nd trip> The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is per-
formed during vehicle operation. Specific on board diagnos tic items will cause the ECM to illuminate or blink
the MIL, and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
DIAGNOSIS DESCRIPTION : DT C and Freeze Frame DataINFOID:0000000006217723
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 saved 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 saved in the 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.
For malfunctions in which 1st trip DTCs are displayed, refer to EC-98, "
DTC Index". These items are required
by legal regulations to continuous ly monitor the system/component. In addi tion, the items monitored non-con-
tinuously are also displayed on CONSULT-III.
1st trip DTC is specified in Service $07 of SAE J1979/ ISO 15031-5. 1st trip DTC detection occurs without illu-
minating the MIL and therefore does not warn the driver of a malfunction.
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-135, "
Work Flow". Then perform DTC Confirma-
tion Procedure or Component Function Check to try to duplicate the malfunction. If the malfunction is dupli-
cated, 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 ca lled 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.
Items MIL DTC 1st trip DTC
1st trip 2nd trip 1st trip
displaying 2nd trip
displaying 1st trip
displaying 2nd trip
displaying
Blinking Illuminate Blinking Illuminate
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0308 is
being detected ×
——— — — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0308 is
being detected ——
×—— ×——
One trip detection diagnoses (Re-
fer to EC-98, "
DTC Index".) —
×—— ×———
Except above — — — ×— ×× —
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Only one set of freeze frame data (either 1st trip freez
e frame data or freeze frame data) can be stored i INFINITI QX56 2011 Factory Service Manual
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Only one set of freeze frame data (either 1st trip freez
e frame data or freeze frame data) can be stored i](/manual-img/42/57033/w960_57033-2076.png)
DIAGNOSIS SYSTEM (ECM)EC-53
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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 tr ip 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, the 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:0000000006217724
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 ti mes (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 v ehicle 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 freeze 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-III will count the number of times the vehicle is driven.
The 1st trip DTC is not displayed when the se lf-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, see “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 malfunction is detected in the 2nd trip.
Relationship Between MIL, DTC, 1st Trip DTC and Dr iving Patterns for “Misfire
terioration>”, “Fuel Injection System”
Priority Items
1 Freeze frame data Misfire — DTC: P0300 - P0308
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
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)
Explanation for Driving Patterns for “Misfire <Exhaust Quality Deterioration>”, “Fuel Injection System”
<Driving Pattern B>
Driving INFINITI QX56 2011 Factory Service Manual
EC-54
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DIAGNOSIS SYSTEM (ECM)
Explanation for Driving Patterns for “Misfire <Exhaust Quality Deterioration>”, “Fuel Injection System”
<Driving Pattern B>
Driving](/manual-img/42/57033/w960_57033-2077.png)
EC-54
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DIAGNOSIS SYSTEM (ECM)
Explanation for Driving Patterns for “Misfire ”, “Fuel Injection System”
Driving pattern B means the vehicl
e operation as per the following:
All components and systems should be monito red at least once by the OBD system.
*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-55
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The B counter will be cleared when the malfunction is
detected once regardless of the driving pattern.
INFINITI QX56 2011 Factory Service Manual
DIAGNOSIS SYSTEM (ECM)EC-55
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The B counter will be cleared when the malfunction is
detected once regardless of the driving pattern.
](/manual-img/42/57033/w960_57033-2078.png)
DIAGNOSIS SYSTEM (ECM)EC-55
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The B counter will be cleared when the malfunction is
detected once regardless of the driving pattern.
The B counter will be counted up when driving pattern B is satisfied without any malfunction.
The MIL will turn OFF when the B counter reaches 3. (*2 in “OBD SYSTEM OPERATION CHART”)
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
Calculated load value: (Calculated load value in the freeze frame data) x (1 ±0.1) [%]
Engine coolant temperature (T) condition:
When the freeze frame data shows lower than 70 °C (158 °F), T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F), T should be higher than or equal to
70 °C (158 °F).
Example:
If the stored freeze frame data is as per the following:
Engine speed: 850 rpm, Calculated load val ue: 30%, Engine coolant temperature: 80°C (176 °F)
To be satisfied with driving pattern C, the v ehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70°C
(158 °F)
The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.
The C counter will be counted up when vehicle conditions above are satisfied without the same malfunction.
The DTC will not be displayed after C counter reaches 80.
The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC is
stored in ECM.
Relationship Between MIL, DTC, 1st Trip DTC and Driving Patterns Except For “Misfire
Quality Deterioration>”, “Fuel Injection System”
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DIAGNOSIS SYSTEM (ECM)
*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.
JMBIA1418GB
Revision: 2010 May2011 QX56