ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-27
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ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
DTC Detection LogicEBS01KCN
When a malfunction is detected, the malfunction (DTC) and freeze frame data are stored in the ECM memory.
The MI will light up each time the ECM detects malfunction. For diagnostic items causing the MI to light up,
refer toEC-6, "
INDEX FOR DTC".
Diagnostic Trouble Code (DTC)EBS01KCO
HOW TO READ DTC
The DTC can be read by the following methods.
With CONSULT-II
CONSULT-IIdisplaystheDTCin"SELF-DIAGRESULTS"mode.Example:P0117,P0335,P1268,etc.These
DTCs are prescribed by ISO15031-5.
(CONSULT-II also displays the malfunctioning component or system.)
Without CONSULT-II
The number of blinks of the MI in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0117, 0335, 1260, etc.
lOutput of a DTC indicates a malfunction. However, the Diagnostic Test Mode II does not indicate
whether the malfunction is still occurring or has occurred in the past and has returned to normal.
CONSULT-II can identify malfunction status as shown below. Therefore, using CONSULT-II (if avail-
able) is recommended.
HOW TO ERASE DTC
With CONSULT-II
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 5
seconds and then turn it ON (engine stopped) again.
2. Touch “ENGINE”.
3. Touch “SELF-DIAG RESULTS”.
4. Touch “ERASE”. (The DTC in the ECM will be erased.)
The emission related diagnostic information in the ECM can be erased by selecting “ERASE” in the “SELF-
DIAG RESULTS” mode with CONSULT-II.
Without CONSULT-II
1. If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once.
2. Wait at least 10 seconds and then turn it ON (engine stopped) again.
3. Change the diagnostic test mode from Mode II to Mode I by depressing the accelerator pedal. Refer to
EC-29, "
HOW TO SWITCH DIAGNOSTIC TEST MODE".
PBIB2452E
EC-28
ON BOARD DIAGNOSTIC (OBD) SYSTEM
lIf the battery is disconnected, the emission-related diagnostic information will be lost within 24
hours.
lThe following data are cleared when the ECM memory is erased.
–Diagnostic trouble codes
–Freeze frame data
–Fuel pump learning value
Actual work procedures are explained using a DTC as an example. Be careful so that not only the DTC, but all
of the data listed above, are cleared from the ECM memory during work procedures.
Freeze Frame DataEBS01KCP
The ECM records the driving conditions such as calculated load value, engine coolant temperature, engine
speed, vehicle speed and intake manifold pressure at the moment a malfunction is detected.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II. For
details, seeEC-28, "
Freeze Frame Data".
Only one set of freeze frame data can be stored in the ECM. If freeze frame data is stored in the ECM memory
and another freeze frame data occurs later, the first (original) freeze frame data remains unchanged in the
ECM memory.
Freeze frame data (along with the DTCs) are cleared when the ECM memory is erased. Procedures for clear-
ing the ECM memory are described inEC-27, "
HOW TO ERASE DTC".
NATS (Nissan Anti-theft System)EBS01KCQ
lIf the security indicator lights up with the ignition switch in
the ON position or "NATS MALFUNCTION" is displayed on
"SELF-DIAG RESULTS" screen, perform self-diagnostic
results mode with CONSULT-II using NATS program card.
Refer toBL-170, "
NATS(Nissan Anti-Theft System)".
lConfirm no self-diagnostic results of NATS is displayed
before touching "ERASE" in "SELF-DAIG RESULTS" mode
with CONSULT-II.
lWhen replacing ECM, initialization of NATS system and reg-
istration of all NATS ignition key IDs must be carried out
with CONSULT-II using NATS program card.
Therefore, be sure to receive all keys from vehicle owner.
Regarding the procedure of NATS initialization and NATS ignition key ID registration, refer to CON-
SULT-II operation manual, NATS.
Malfunction Indicator (MI)EBS01KCR
DESCRIPTION
The MI is located on the combination meter.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
lIf the MI does not light up, refer toEC-354, "MI&DATA LINK
CONNECTORS".
2. When the engine is started, the MI should go off.
If the MI remains on, the on board diagnostic system has
detected an engine system malfunction.
ON BOARD DIAGNOSTIC SYSTEM FUNCTION
The on board diagnostic system has the following three functions.
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
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HOWTOSWITCHDIAGNOSTICTESTMODE
NOTE:
lIt is better to count the time accurately with a clock.
lIt is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.
lAlways 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 released, 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 MI starts
blinking.
4. Fully release the accelerator pedal.
ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).
Diagnostic Test
ModeKEY and ENG.
Statu sFunction Explanation of Function
Mode I Ignition switch in
ON position
Engine stoppedBULB CHECK This function checks the MI bulb for damage (blown, open
circuit, etc.).
If the MI does not come on, check MI circuit. (SeeEC-354,
"MI&DATA LINK CONNECTORS".)
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When ECM detects a mal-
function, the MI will light up to inform the driver that a mal-
function has been detected.
Mode II Ignition switch in
ON position
Engine stoppedSELF-DIAGNOSTIC
RESULTSThis function allows DTCs to be read.
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TROUBLE DIAGNOSIS
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TROUBLE DIAGNOSISPFP:00004
Trouble Diagnosis IntroductionEBS01KCT
INTRODUCTION
The engine has an ECM to control major systems such as fuel injec-
tion control, fuel injection timing control, glow control system, etc.
The ECM accepts input signals from sensors and instantly actuators.
It is essential that both input and output signals are proper and sta-
ble. At the same time, it is important that there are no malfunctions
such as vacuum leaks, or other malfunctions with the engine.
It is much more difficult to diagnose a malfunction that occurs inter-
mittently rather than continuously. Most intermittent malfunctions are
caused by poor electric connections or improper wiring. In this case,
careful checking of suspected circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the incidents. A road
test with CONSULT-II or a circuit tester connected should be per-
formed. Follow theEC-34, "
WORK FLOW".
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such incidents, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A Diagnostic Worksheet like the example
on next page should be used.
Start your diagnosis by looking for “conventional” incidents first. This
will help troubleshoot driveability incidents on an electronically con-
trolled engine vehicle.
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TROUBLE DIAGNOSIS
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Description for Work Flow
DIAGNOSTIC WORK SHEET
There are many operating conditions that lead to the malfunction of
engine components. A good grasp of such conditions can make trou-
bleshooting faster and more accurate.
In general, each customer feels differently about an incident. It is
important to fully understand the symptoms or conditions for a cus-
tomer complaint.
Utilize a diagnostic worksheet like the one shown below in order to
organize all the information for troubleshooting.
STEP DESCRIPTION
STEP IGet detailed information about the conditions and the environment when the incident/symptom occurred using the
EC-35, "
DIAGNOSTIC WORK SHEET".
STEP IIBefore confirming the concern, check and write down (print out using CONSULT-II) the DTC and the freeze frame
data, then erase the DTC. The DTC and the freeze frame data can be used when duplicating the incident at STEP III
&IV.RefertoEC-27
.
If the incident cannot be verified, performEC-70, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT".
Study the relationship between the cause, specified by DTC, and the symptom described by the customer. (The
“Symptom Matrix Chart” will be useful. Refer toEC-42
.) Also check related service bulletins for information.
STEP IIITry to confirm the symptom and under what conditions the incident occurs.
The “DIAGNOSTIC WORK SHEET” and the freeze frame data are useful to verify the incident. Connect CONSULT-II
to the vehicle in DATA MONITOR (AUTO TRIG) mode and check real time diagnosis results.
If the incident cannot be verified, performEC-70, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT".
If the malfunction code is detected, skip STEP IV and perform STEP V.
STEP IVTry to detect the DTC by driving in (or performing) the DTC Confirmation Procedure. Check and read the DTC and the
freeze frame data by using CONSULT-II.
During the DTC verification, be sure to connect CONSULT-II to the vehicle in DATA MONITOR (AUTO TRIG) mode
and check real time diagnosis results.
If the incident cannot be verified, performEC-70, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT".
In case the DTC Confirmation Procedure is not available, perform the Overall Function Check instead. The DTC can-
not be displayed by this check, however, this simplified “check” is an effective alternative.
The “NG” result of the Overall Function Check is the same as the DTC detection.
STEP VTake the appropriate action based on the results of STEP I through IV.
If the malfunction code is indicated, proceed to Trouble Diagnosis for DTC PXXXX.
If the normal code is indicated, proceed to the Basic Inspection,EC-38
. Then perform inspections according to the
Symptom Matrix Chart. Refer toEC-42
.
STEP VIIdentify where to begin diagnosis based on the relationship study between symptom and possible causes. Inspect the
system for mechanical binding, loose connectors or wiring damage using (tracing) Harness Layouts.
Gently shake the related connectors, components or wiring harness with CONSULT-II set in “DATA MONITOR (AUTO
TRIG)” mode.
Check the voltage of the related ECM terminals or monitor the output data from the related sensors with CONSULT-II.
Refer toEC-52
orEC-66.
The Diagnostic Procedure in EC section contains a description based on open circuit inspection. A short circuit
inspection is also required for the circuit check in the Diagnostic Procedure. For details, refer toGI-24, "
How to Per-
form Efficient Diagnosis for an Electrical Incident", “Circuit Inspection”.
Repair or replace the malfunction parts.
If the malfunctioning part cannot be detected, performEC-70, "
TROUBLE DIAGNOSIS FOR INTERMITTENT INCI-
DENT".
STEP VIIOnce you have repaired the circuit or replaced a component, you need to run the engine in the same conditions and
circumstances which resulted in the customer's initial complaint.
Perform the DTC Confirmation Procedure and confirm the normal code (DTC P0000) is detected. If the incident is still
detected in the final check, perform STEP VI by using a different method from the previous one.
Before returning the vehicle to the customer, be sure to erase the unnecessary (already fixed) DTC in ECM. (Refer to
EC-27
.)
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TROUBLE DIAGNOSIS
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DTC Inspection Priority ChartEBS01KCU
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC U1000 is displayed with other DTC, first perform the trouble diagnosis for DTC U1000. Refer to
EC-79, "
DTC U1000 CAN COMMUNICATION LINE".
Priority Detected items (DTC)
1
lU1000 CAN communication line
lP0016 Crankshaft position - camshaft position correlation
lP0102 P0103 Mass air flow sensor
lP0112 P0113 Intake air temperature sensor
lP0117 P0118 Engine coolant temperature sensor
lP0122 P0123 P0222 P0223 P2135 Accelerator pedal position sensor
lP0182 P0183 Fuel pump temperature sensor
lP0192 P0193 Fuel rail pressure sensor
lP0237 P0238 Turbocharger boost sensor
lP0335 P0336 Crankshaft position sensor
lP0340 P0341 Camshaft position sensor
lP0563 Battery voltage
lP0605 P0606 P1616 ECM
lP0642 P0643 P0652 P0653 Sensor power supply
lP1610 - P1615 NATS
lP1622 P1623 Injector adjustment value
lP2228 P2229 Barometric pressure sensor
2
lP0089 P0628 P0629 P1272 - P1275 Fuel pump
lP0200 - P0204 P1268 - P1271 P2146 - P2149 Fuel injector
lP0686 ECM relay
3
lP0088 P0093 Fuel system
lP0217 Engine over temperature (OVERHEAT)
lP0234 Turbocharger system
lP0501 P0502 P0503 ASCD vehicle speed sensor
lP0504 ASCD brake switch
lP0580 P0581 ASCD steering switch
EC-38
TROUBLE DIAGNOSIS
Basic Inspection
EBS01KCV
Precaution:
Perform Basic Inspection without electrical or mechanical loads applied;
lHeadlamp switch is OFF.
lOn vehicles equipped with daytime light systems, set lighting switch to the 1st position to light
only small lamps.
lAir conditioner switch is OFF.
lHeater fan switch is OFF.
lRear defogger switch is OFF.
lHeat up switch is OFF.
lSteering wheel is in the straight-ahead position, etc.
1.INSPECTION START
1. Check service records for any recent repairs that may indicate a related incident.
2. Check the current need for scheduled maintenance, especially for fuel filter and air cleaner filter. Refer to
MA-8, "
PERIODIC MAINTENANCE".
3. Open engine hood and check the following:
–Harness connectors for improper connections
–Vacuum hoses for splits, kinks, or improper connections
–Wiring for improper connections, pinches, or cuts
4. Start engine and warm it up to the normal operating tempera-
ture.
>> GO TO 2.
2.PREPARATION FOR CHECKING IDLE SPEED
With CONSULT-II
Connect CONSULT-II to the data link connector.
Without CONSULT-II
Install diesel tacho tester to the vehicle.
>> GO TO 3.
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3.CHECK IDLE SPEED
With CONSULT-II
1. Select “CKPS·RPM (TDC)” in “DATA MONITOR” mode with CONSULT-II.
2. Read idle speed.
Without CONSULT-II
Read idle speed.
OK or NG
OK >>INSPECTION END
NG >> GO TO 4.
4.CHECK FOR INTAKE AIR LEAK
1. Stop engine.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace.
5.BLEED AIR FROM FUEL SYSTEM
Use priming pump to bleed air from fuel system. Refer toEC-23, "
AIR BLEEDING".
>> GO TO 6.
6.CHECK IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and let it idle.
2. Select “CKPS·RPM (TDC)” in “DATA MONITOR” mode with CONSULT-II.
3. Read idle speed.
Without CONSULT-II
Read idle speed.
OK or NG
OK >>INSPECTION END
NG >> GO TO 7.
7.DRAIN WATER FROM FUEL FILTER
1. Stop engine.
2. Drain water from fuel filter. Refer toEC-23, "
WATER DRAINING".
>> GO TO 8. M/T: 750±25 rpm (in Neutral position)
A/T: 750±25 rpm (in P or N position)
M/T: 750±25 rpm (in Neutral position)
A/T: 750±25 rpm (in P or N position)
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M/T: 750±25 rpm (in Neutral position)
A/T: 750±25 rpm (in P or N position)
M/T: 750±25 rpm (in Neutral position)
A/T: 750±25 rpm (in P or N position)
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