SERVICE INFORMATION FOR ELECTRICAL INCIDENT
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If repairs are needed always use wire that is of the same or larger gauge.
MEASURING VOLTAGE DROP — ACCUMULATED METHOD
●Connect the DMM across the connector or part of the circuit you want to check. The positive lead of the
DMM should be closer to power and the negative lead closer to ground.
●Operate the circuit.
●The DMM will indicate how many volts are being used to “push” current through that part of the circuit.
Note in the illustration that there is an excessive 4.1 volt drop between the battery and the bulb.
MEASURING VOLTAGE DROP — STEP-BY-STEP
The step-by-step method is most useful for isolating excessive drops in low voltage systems (such as those in
“Computer Controlled Systems”).
Circuits in the “Computer Controlled System” operate on very low amperage.
The (Computer Controlled) system operations can be adversely affected by any variation in resistance in the
system. Such resistance variation may be caused by poor connection, improper installation, improper wire
gauge or corrosion.
The step by step voltage drop test can identify a component or wire with too much resistance.
SGI974
SAIA0258E
EC-58
[QR25(WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
5. System readiness test (SRT) codes
6. Test values
7. Others
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.
NATS (Nissan Anti-theft System)EBS00M0P
●If 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 to BL-80, "
NATS (NISSAN ANTI-THEFT SYSTEM)" .
●Confirm no self-diagnostic results of NATS is displayed
before touching “ERASE” in “SELF-DIAG RESULTS” mode
with CONSULT-II.
●When 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 procedures of NATS initialization and NATS ignition key ID registration, refer to
CONSULT-II operation manual, NATS.
Malfunction Indicator (MI)EBS00M0Q
DESCRIPTION
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
●If the MI does not light up, refer to DI-43, "WARNING LAMPS" ,
or see EC-263
.
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 four functions.
SEF515Y
SAT652J
Diagnostic Test
ModeKEY and ENG.
Sta tusFunction 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.
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MI will light up to inform the driver that
a malfunction has been detected.
The following malfunctions will light up or blink the MI in
the 1st trip.
●“Misfire (Possible three way catalyst damage)”
●“One trip detection diagnoses”
EC-60
[QR25(WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
ECM has entered to Diagnostic Test Mode II (Self-diagnostic results).
How to Set Diagnostic Test Mode II (Heated Oxygen Sensor 1 Monitor)
1. Set the ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to EC-59, "How to Set Diagnostic
Test Mode II (Self-diagnostic Results)" .
2. Start Engine.
ECM has entered to Diagnostic Test Mode II (Heated oxygen sensor 1 monitor).
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
1. Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to EC-59, "How to Set Diagnostic Test
Mode II (Self-diagnostic Results)" .
2. Fully depress the accelerator pedal and keep it for more than 10 seconds.
The emission-related diagnostic information has been erased from the backup memory in the ECM.
3. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
DIAGNOSTIC TEST MODE I — BULB CHECK
In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to DI-43,
"WARNING LAMPS" or see EC-263 .
DIAGNOSTIC TEST MODE I — MALFUNCTION WARNING
●These DTC numbers are clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)
DIAGNOSTIC TEST MODE II — SELF-DIAGNOSTIC RESULTS
In this mode, the DTC and 1st trip DTC are indicated by the number of blinks of the MI as shown below.
The DTC and 1st trip DTC are displayed at the same time. If the MI does not illuminate in diagnostic test mode
I (Malfunction warning), all displayed items are 1st trip DTCs. If only one code is displayed when the MI illumi-
nates in diagnostic test mode II (SELF-DIAGNOSTIC RESULTS), it is a DTC; if two or more codes are dis-
played, they may be either DTCs or 1st trip DTCs. DTC No. is same as that of 1st trip DTC. These unidentified
PBIB0092E
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
DTC P0650 MI
EC-263
[QR25(WITH EURO-OBD)]
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EC
DTC P0650 MIPFP:24810
Component DescriptionEBS00M6Q
Malfunction Indicator (MI) is located on the instrument panel. When the ignition switch is turned ON without
engine running, MI will light up. This is a bulb check. When the engine is started, MI should go off. If MI
remains on, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnosis LogicEBS00M6R
FAIL-SAFE MODE
ECM enters fail-safe mode when both DTC P0650 and another DTC, which calls for MI to light up, are
detected at the same time.
DTC Confirmation ProcedureEBS00M6S
NOTE:
If “DTC Confirmation Procedure” has been previously conducted, always turn ignition switch “OFF” and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch “ON” and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If 1st trip DTC is detected, go to EC-265, "
Diagnostic Procedure"
.
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0650
0650Malfunction indicator
(MI) control circuit
●An excessively high voltage is sent to ECM
through the MI circuit under the condition
that calls for MI light up.
●An excessively low voltage is sent to ECM
through the MI circuit under the condition
that calls for MI not to light up.
●Harness or connectors
(MI circuit is open or shorted.)
●MI
Detected items Engine operating condition in fail-safe mode
MI circuit Engine speed will not rise more than 2,500 rpm due to the fuel cut
SEF058Y
ON BOARD DIAGNOSTIC (OBD) SYSTEM
EC-457
[QR25(WITHOUT EURO-OBD)]
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Malfunction Indicator (MI)EBS00NE8
DESCRIPTION
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
●If the MI does not light up, refer to DI-43, "WARNING LAMPS" ,
or see EC-1265
.
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 four functions.
MI Flashing without DTC
If the ECM is in Diagnostic Test Mode II, MI may flash when engine is running. In this case, check ECM diag-
nostic test mode. EC-458, "
HOW TO SWITCH DIAGNOSTIC TEST MODE" .
How to switch the diagnostic test (function) modes, and details of the above functions are described later EC-
458 .
The following emission-related diagnostic information is cleared when the ECM memory is erased.
1. Diagnostic trouble codes
2. 1st trip diagnostic trouble codes
3. Freeze frame data
SAT652J
Diagnostic Test
ModeKEY and ENG.
StatusFunction 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.
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MI will light up to inform the driver that
a malfunction has been detected.
The following malfunctions will light up the MI in the 1st
trip.
●Fail-safe mode
Mode II Ignition switch in
“ON” position
Engine stoppedSELF-DIAGNOSTIC
RESULTSThis function allows DTCs and 1st trip DTCs to be read.
Engine running HEATED OXYGEN SENSOR 1
MONITORThis function allows the fuel mixture condition (lean or
rich), monitored by heated oxygen sensor 1, to be read.
EC-458
[QR25(WITHOUT EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
4. 1st trip freeze frame data
5. Others
HOW TO SWITCH DIAGNOSTIC TEST 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 malfunction.
●Always 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).
How to Set Diagnostic Test Mode II (Heated Oxygen Sensor 1 Monitor)
1. Set the ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to EC-458, "How to Set Diagnostic
Test Mode II (Self-diagnostic Results)" .
2. Start Engine.
ECM has entered to Diagnostic Test Mode II (Heated oxygen sensor 1 monitor).
How to Erase Diagnostic Test Mode II (Self-diagnostic Results)
1. Set ECM in Diagnostic Test Mode II (Self-diagnostic results). Refer to EC-458, "How to Set Diagnostic
Test Mode II (Self-diagnostic Results)" .
2. Fully depress the accelerator pedal and keep it for more than 10 seconds.
The emission-related diagnostic information has been erased from the backup memory in the ECM.
3. Fully release the accelerator pedal, and confirm the DTC 0000 is displayed.
DIAGNOSTIC TEST MODE I — BULB CHECK
In this mode, the MI on the instrument panel should stay ON. If it remains OFF, check the bulb. Refer to DI-43,
"WARNING LAMPS" or see EC-1265 .
DIAGNOSTIC TEST MODE I — MALFUNCTION WARNING
●These DTC numbers are clarified in Diagnostic Test Mode II (SELF-DIAGNOSTIC RESULTS)
PBIB0092E
MI Condition
ON When the malfunction is detected or the ECM's CPU is malfunctioning.
OFF No malfunction.
EC-576
[QR25(WITHOUT EURO-OBD)]
DTC P0650 MI
DTC P0650 MI
PFP:24810
Component DescriptionEBS00NHA
Malfunction Indicator (MI) is located on the instrument panel. When the ignition switch is turned ON without
engine running, MI will light up. This is a bulb check. When the engine is started, MI should go off. If MI
remains on, the on board diagnostic system has detected an engine system malfunction.
On Board Diagnosis LogicEBS00NHB
FAIL-SAFE MODE
ECM enters fail-safe mode when both DTC P0650 and another DTC, which calls for MI to light up, are
detected at the same time.
DTC Confirmation ProcedureEBS00NHC
NOTE:
If “DTC Confirmation Procedure” has been previously conducted, always turn ignition switch “OFF” and wait at
least 10 seconds before conducting the next test.
WITH CONSULT-II
1. Turn ignition switch “ON” and wait at least 1 second.
2. Select “DATA MONITOR” mode with CONSULT-II.
3. Start engine and let it idle for 1 second.
4. If 1st trip DTC is detected, go to EC-578, "
Diagnostic Procedure"
.
Overall Function CheckEBS00O2O
Use this procedure to check the overall function of the MI circuit. During this check, a 1st trip DTC might not be
confirmed.
WITHOUT CONSULT-II
1. Turn ignition switch “ON”.
2. Check that the MI is illuminated.
3. If NG, go to EC-578, "
Diagnostic Procedure" .
If OK, go to next step.
4. Start engine.
5. Check that the MI is not illuminated.
6. If NG, go to EC-578, "
Diagnostic Procedure" .
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P0650
0650Malfunction indicator
(MI) control circuit
●An excessively high voltage is sent to ECM
through the MI circuit under the condition
that calls for MI light up.
●An excessively low voltage is sent to ECM
through the MI circuit under the condition
that calls for MI not to light up.
●Harness or connectors
(MI circuit is open or shorted.)
●MI
Detected items Engine operating condition in fail-safe mode
MI circuit Engine speed will not rise more than 2,500 rpm due to the fuel cut
SEF058Y
EC-790
[QR20(WITH EURO-OBD)]
ON BOARD DIAGNOSTIC (OBD) SYSTEM
5. System readiness test (SRT) codes
6. Test values
7. Others
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.
NATS (Nissan Anti-theft System)EBS00MSO
●If 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 to BL-80, "
NATS (NISSAN ANTI-THEFT SYSTEM)" .
●Confirm no self-diagnostic results of NATS is displayed
before touching “ERASE” in “SELF-DIAG RESULTS” mode
with CONSULT-II.
●When 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 procedures of NATS initialization and NATS ignition key ID registration, refer to
CONSULT-II operation manual, NATS.
Malfunction Indicator (MI)EBS00MSP
DESCRIPTION
The MI is located on the instrument panel.
1. The MI will light up when the ignition switch is turned ON without
the engine running. This is a bulb check.
●If the MI does not light up, refer to DI-43, "WARNING LAMPS" ,
or see EC-991
.
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 four functions.
SEF515Y
SAT652J
Diagnostic Test
ModeKEY and ENG.
Sta tusFunction 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.
Engine running MALFUNCTION
WARNINGThis is a usual driving condition. When a malfunction is
detected twice in two consecutive driving cycles (two trip
detection logic), the MI will light up to inform the driver that
a malfunction has been detected.
The following malfunctions will light up or blink the MI in
the 1st trip.
●“Misfire (Possible three way catalyst damage)”
●“One trip detection diagnoses”