NISSAN ALMERA 2001 Service Manual
Page 901 of 2898
DescriptionNJEC0045Intermittent incidents (I/I) may occur. In many cases, the problem resolves itself (the part or circuit function
returns to normal without intervention). It is important to realize that the symptoms described in the custom-
er's complaint often do not recur on DTC (1st trip) visits. Realize also that the most frequent cause of I/I
occurrences is poor electrical connections. Because of this, the conditions under which the incident occurred
may not be clear. Therefore, circuit checks made as part of the standard diagnostic procedure may not indi-
cate the specific problem area.
COMMON I/I REPORT SITUATIONSNJEC0045S01
STEP in Work Flow Situation
IIThe CONSULT-II is used. The SELF-DIAG RESULTS screen shows time data other than ª0º or
ª1tº.
III The symptom described by the customer does not recur.
IV (1st trip) DTC data does not appear during the DTC Confirmation Procedure.
VI The Diagnostic Procedure for PXXXX does not indicate the problem area.
Diagnostic ProcedureNJEC0046
1 INSPECTION START
Erase (1st trip) DTCs. Refer to ªHow to Erase Emission-related Diagnostic Informationº, EC-70, EC-73.
©GO TO 2.
2 CHECK GROUND TERMINALS
Check ground terminals for corroding or loose connection. Refer to GI-27, ªGROUND INSPECTIONº.
OK or NG
OK©GO TO 3.
NG©Repair or replace.
3 SEARCH FOR ELECTRICAL INCIDENT
Perform GI-22, ªIncident Simulation Testsº.
OK or NG
OK©INSPECTION END
NG©Repair or replace.
TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTQG
Description
EC-177
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Main Power Supply and Ground Circuit
WIRING DIAGRAMNJEC0047Sedan models and Hatchback Models with ECM in Engine CompartmentNJEC0047S01
HEC779
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit
EC-178
Page 903 of 2898
Hatchback Models with ECM in CabinNJEC0047S02
HEC972
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-179
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HEC955
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-180
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ECM TERMINALS AND REFERENCE VALUENJEC0048Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
TERMI-
NAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
31 W/G ECM relay (Self shut-off)[Engine is running]
[Ignition switch ªOFFº]
+For 9 seconds after turning ignition switch ªOFFº0-1V
[Ignition switch ªOFFº]
+9 seconds passed after turning ignition switch
ªOFFºBATTERY VOLTAGE
(11 - 14V)
43 B/R Ignition switch[Ignition switch ªOFFº]0V
[Ignition switch ªONº]BATTERY VOLTAGE
(11 - 14V)
48 B ECM ground[Engine is running]
+Idle speedEngine ground
57 B ECM ground[Engine is running]
+Idle speedEngine ground
67 W/LPower supply for ECM
(Back-up)[Ignition switch ªOFFº]BATTERY VOLTAGE
(11 - 14V)
106
108B/Y
B/YECM ground[Engine is running]
+Idle speedEngine ground
11 0
11 2W
WPower supply for ECM[Ignition switch ªONº]BATTERY VOLTAGE
(11 - 14V)
DIAGNOSTIC PROCEDURENJEC0565
1 INSPECTION START
Start engine.
Is engine running?
YesorNo
Ye s©GO TO 9.
No©GO TO 2.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-181
Page 906 of 2898
2 CHECK ECM POWER SUPPLY CIRCUIT-I
1. Turn ignition switch ªOFFº and then ªONº.
2. Check voltage between ECM terminal 43 and ground with CONSULT-II or tester.
SEF291X
OK or NG
OK©GO TO 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E74, F35 (If so equipped)
+Harness connectors M21, E106 (Sedan), M160, E175 or M169, F113 (Hatchback)
+Fuse block (J/B) connector M1, E103
+10A fuse
+Harness for open or short between ECM and ignition switch
©Repair harness or connectors.
4 CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 48, 57, 106, 108 and engine ground.
Refer to WIRING DIAGRAM.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 5.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-182
Page 907 of 2898
5 CHECK POWER SUPPLY-II
1. Disconnect ECM relay. (For ECM relay location, refer to ªEngine Control Compartment Parts Locationº.)
2. Check voltage between ECM relay terminals 1, 6 and ground with CONSULT-II or tester.
SEF101Y
OK or NG
OK©GO TO 7.
NG©GO TO 6.
6 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse and 10A fuse
+Harness connectors E75, F36 (If so equipped)
+Harness for open or short between ECM relay and battery
©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1. Check harness continuity between ECM terminal 31 and ECM relay terminal 2.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©Go to ªIGNITION SIGNALº, EC-547.
NG©GO TO 8.
8 DETECT MALFUNCTIONING PART
Check the harness for open or short between ECM relay and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-183
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9 CHECK ECM POWER SUPPLY CIRCUIT-II
1. Stop engine.
2. Check voltage between ECM terminal 67 and ground with CONSULT-II or tester.
SEF293X
OK or NG
OK©GO TO 11.
NG©GO TO 10.
10 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E75, F36 (If so equipped)
+Harness for open or short between ECM and fuse
©Repair harness or connectors.
11 CHECK ECM POWER SUPPLY CIRCUIT-III
1. Turn ignition switch ªONº and then ªOFFº.
2. Check voltage between ECM terminals 110, 112 and ground with CONSULT-II or tester.
SEF294X
OK or NG
OK©GO TO 17.
NG (Battery voltage
does not exist.)©GO TO 12.
NG (Battery voltage
exists for more than a
few seconds.)©GO TO 14.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-184
Page 909 of 2898
12 CHECK ECM POWER SUPPLY CIRCUIT-IV
1. Disconnect ECM relay. (For ECM relay location, refer to ªEngine Control Compartment Parts Locationº.)
2. Check voltage between ECM relay terminal 3 or 5 (only ECM relay in relay box) and ground with CONSULT-II or tester.
YEC048A
OK or NG
OK©GO TO 14.
NG©GO TO 13.
13 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors E75, F36 (If so equipped)
+Harness for open or short between ECM relay and 10A fuse
©Repair open circuit or short to ground or short to power in harness or connectors.
14 CHECK HARNESS CONTINUITY BETWEEN ECM RELAY AND ECM FOR OPEN AND SHORT
1. Check harness continuity between ECM terminals 110, 112 and ECM relay terminal 5 or 3 (only ECM relay in relay
box).
Refer to WIRING DIAGRAM.
Continuity should exist.
2. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 16.
NG©GO TO 15.
15 DETECT MALFUNCTIONING PART
Check the following.
+Joint connector-4 (If so equipped)
+Joint connector-6 (If so equipped)
+Harness connector E75, F36 (If so equipped)
+Harness for open or short between ECM and ECM relay
©Repair open circuit or short to ground or short to power in harness or connectors.
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-185
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16 CHECK ECM RELAY
1. Apply 12V direct current between ECM relay terminals 1 and 2.
2. Check continuity between relay terminals 3 and 5, 6 and 7.
SEF296X
OK or NG
OK©GO TO 17.
NG©Replace ECM relay.
17 CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between ECM terminals 48, 57, 106, 108 and engine ground.
Refer to WIRING DIAGRAM.
Continuity should exist.
4. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 18.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
18 CHECK INTERMITTENT INCIDENT
Refer to ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-177.
©INSPECTION END
TROUBLE DIAGNOSIS FOR POWER SUPPLYQG
Main Power Supply and Ground Circuit (Cont'd)
EC-186