Page 541 of 2493
Wiring DiagramNJEC0185
YEC970
DTC P0141 HEATED OXYGEN SENSOR 2 HEATER (REAR)QG
Wiring Diagram
EC-245
Page 542 of 2493

Diagnostic ProcedureNJEC0186
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 2 (rear) harness connector.
NEF345A
3. Turn ignition switch ªONº.
4. Check voltage between terminal 2 and ground.
SEF218W
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
+Harness connectors M169, F113
+Harness for open or short between heated oxygen sensor 2 (rear) and fuse
+10A fuse
©Repair harness or connectors.
3 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between heated oxygen sensor 2 (rear) harness connector terminal 3 and ECM terminal 3.
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©GO TO 4.
4 DETECT MALFUNCTIONING PART
Check the harness for open or short between heated oxygen sensor 2 heater (rear) and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0141 HEATED OXYGEN SENSOR 2 HEATER (REAR)QG
Diagnostic Procedure
EC-246
Page 546 of 2493
Wiring DiagramNJEC0190
YEC971
DTC P0171 FUEL INJECTION SYSTEM FUNCTION (LEAN SIDE)QG
Wiring Diagram
EC-250
Page 547 of 2493

Diagnostic ProcedureNJEC0191
1 CHECK EXHAUST AIR LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust air leak before three way catalyst.
SEF099P
OK or NG
OK©GO TO 2.
NG©Repair or replace.
2 CHECK FOR INTAKE AIR LEAK
Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK©GO TO 3.
NG©Repair or replace.
3 CHECK HEATED OXYGEN SENSOR 1 (FRONT) CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 1 (front) harness connector and ECM harness connector.
SEF012XA
3. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
4. Check harness continuity between ECM terminal 62 [or heated oxygen sensor 1 (front) harness connector terminal 2]
and ground.
Continuity should not exist.
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 4.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0171 FUEL INJECTION SYSTEM FUNCTION (LEAN SIDE)QG
Diagnostic Procedure
EC-251
Page 553 of 2493
Wiring DiagramNJEC0194
YEC971
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Wiring Diagram
EC-257
Page 554 of 2493
Diagnostic ProcedureNJEC0195
1 CHECK FOR EXHAUST AIR LEAK
1. Start engine and run it at idle.
2. Listen for an exhaust air leak before the three way catalyst.
SEF099P
OK or NG
OK©GO TO 2.
NG©Repair or replace.
2 CHECK HEATED OXYGEN SENSOR 1 (FRONT) CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect heated oxygen sensor 1 (front) harness connector and ECM harness connector.
SEF012XA
3. Check harness continuity between ECM terminal 62 and heated oxygen sensor 1 (front) harness connector terminal 2.
Refer to wiring diagram.
Continuity should exist.
4. Check harness continuity between ECM terminal 62 [or heated oxygen sensor 1 (front) harness connector terminal 2]
and ground.
Continuity should not exist.
5. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 3.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0172 FUEL INJECTION SYSTEM FUNCTION (RICH SIDE)QG
Diagnostic Procedure
EC-258
Page 565 of 2493
Wiring DiagramNJEC0210
YEC972
DTC P0325 KNOCK SENSOR (KS)QG
Wiring Diagram
EC-269
Page 566 of 2493
Diagnostic ProcedureNJEC0211
1 RETIGHTEN GROUND SCREWS
Loosen and retighten engine ground screws.
JEF104Y
©GO TO 2.
2 CHECK INPUT SIGNAL CIRCUIT-1
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector and knock sensor harness connector.
JEF110Y
3. Check harness continuity between knock sensor signal terminal 1 and ECM terminal 81.
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 4.
NG©GO TO 3.
3 DETECT MALFUNCTIONING PART
Check the harness for open or short between knock sensor and ECM.
©Repair open circuit or short to ground or short to power in harness or connectors.
4 CHECK KNOCK SENSOR
Refer to ªComponent Inspectionº, EC-271.
OK or NG
OK©GO TO 5.
NG©Replace knock sensor.
DTC P0325 KNOCK SENSOR (KS)QG
Diagnostic Procedure
EC-270