Page 1128 of 3051
Wiring DiagramNLEC1410MODELS WITH ECM IN ENGINE COMPARTMENTNLEC1410S01
YEC690
DTC P0120 THROTTLE POSITION SENSORSR20DE
Wiring Diagram
EC-703
Page 1129 of 3051
MODELS WITH ECM IN CABINNLEC1410S02
YEC915
DTC P0120 THROTTLE POSITION SENSORSR20DE
Wiring Diagram (Cont'd)
EC-704
Page 1131 of 3051

4 CHECK GROUND CIRCUIT
1. Turn ignition switch ªOFFº.
2. Check harness continuity between throttle position sensor terminal 1 and engine ground.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to power.
OK or NG
OK©GO TO 6.
NG©GO TO 5.
5 DETECT MALFUNCTIONING PART
Check the following.
+Joint connector-1 (where fitted)
+Joint connector F46 (where fitted)
+Harness for open or short between ECM terminal 58 and throttle position sensor
+Harness for open or short between ECM terminal 58 and TCM (Transmission Control Module)
©Repair open circuit or short to power in harness or connectors.
6 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 92 and throttle position sensor terminal 2.
Refer to wiring diagram.
Continuity should exist.
3. Also check harness for short to ground and short to power.
OK or NG
OK©GO TO 7.
NG©Repair open circuit or short to ground or short to power in harness or connectors.
7 CHECK THROTTLE POSITION SENSOR
Refer to ªComponent Inspectionº, EC-707.
OK or NG
OK©GO TO 8.
NG©Replace throttle position sensor. To adjust it, perform ªBasic Inspectionº, EC-623.
8 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
DTC P0120 THROTTLE POSITION SENSORSR20DE
Diagnostic Procedure (Cont'd)
EC-706
Page 1137 of 3051
Wiring DiagramNLEC1419MODELS WITH ECM IN ENGINE COMPARTMENTNLEC1419S03
YEC691
DTC P0130 HEATED OXYGEN SENSOR 1 (FRONT) (CIRCUIT)SR20DE
Wiring Diagram
EC-712
Page 1138 of 3051
MODELS WITH ECM IN CABINNLEC1419S04
YEC916
DTC P0130 HEATED OXYGEN SENSOR 1 (FRONT) (CIRCUIT)SR20DE
Wiring Diagram (Cont'd)
EC-713
Page 1139 of 3051

Diagnostic ProcedureNLEC1420
1 INSPECTION START
1. Turn ignition switch ªOFFº.
2. Loosen and retighten engine ground screws.
SEF202X
3. Disconnect heated oxygen sensor 1 (front) harness connector.
SEF774Z
©GO TO 2.
2 CHECK INPUT SIGNAL CIRCUIT
1. Disconnect ECM harness connector.
2. Check harness continuity between ECM terminal 62 and HO2S1 terminal 2.
Refer to wiring diagram.
Continuity should exist.
3. Check harness continuity between ECM terminal 62 (or HO2S1 terminal 2) and ground.
Continuity should not exist.
4. Also check harness for 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.
3 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
Refer to ªComponent Inspectionº, EC-715.
OK or NG
OK©GO TO 4.
NG©Replace heated oxygen sensor 1 (front).
4 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
DTC P0130 HEATED OXYGEN SENSOR 1 (FRONT) (CIRCUIT)SR20DE
Diagnostic Procedure
EC-714
Page 1146 of 3051

4 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
Refer to ªComponent Inspectionº, EC-721.
OK or NG
OK©GO TO 5.
NG©Replace heated oxygen sensor 1 (front).
5 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
Refer to ªWiring Diagramº, EC-712, for circuit.
©INSPECTION END
SEF646Y
SEF217YA
Component InspectionNLEC1429HEATED OXYGEN SENSOR 1 (FRONT)NLEC1429S01With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Select ªMANU TRIGº in ªDATA MONITORº mode, and select
ªHO2S1 (B1)º and ªHO2S1 MNTR (B1)º.
3) Hold engine speed at 2,000 rpm under no load during the fol-
lowing steps.
4) Touch ªRECORDº on CONSULT-II screen.
5) Check the following.
+ªHO2S1 MNTR (B1)º in ªDATA MONITORº mode changes from
ªRICHº to ªLEANº to ªRICHº 5 times in 10 seconds.
5 times (cycles) are counted as shown below:
R = ªHO2S1 MNTR (B1)º, ªRICHº
L = ªHO2S1 MNTR (B1)º, ªLEANº
+ªHO2S1 (B1)º voltage goes above 0.6V at least once.
+ªHO2S1 (B1)º voltage goes below 0.3V at least once.
+ªHO2S1 (B1)º voltage never exceeds 1.0V.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
DTC P0131 HEATED OXYGEN SENSOR 1 (FRONT) (LEAN SHIFT
MONITORING)
SR20DE
Diagnostic Procedure (Cont'd)
EC-721
Page 1152 of 3051

4 CHECK HEATED OXYGEN SENSOR 1 HEATER (FRONT)
Refer to ªComponent Inspectionº, EC-751.
OK or NG
OK©GO TO 5.
NG©Replace heated oxygen sensor 1 (front).
5 CHECK HEATED OXYGEN SENSOR 1 (FRONT)
Refer to ªComponent Inspectionº, EC-727.
OK or NG
OK©GO TO 6.
NG©Replace heated oxygen sensor 1 (front).
6 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
Refer to ªWiring Diagramº, EC-712, for circuit.
©INSPECTION END
SEF646Y
SEF217YA
Component InspectionNLEC1437HEATED OXYGEN SENSOR 1 (FRONT)NLEC1437S01With CONSULT-II
1) Start engine and warm it up to normal operating temperature.
2) Select ªMANU TRIGº in ªDATA MONITORº mode, and select
ªHO2S1 (B1)º and ªHO2S1 MNTR (B1)º.
3) Hold engine speed at 2,000 rpm under no load during the fol-
lowing steps.
4) Touch ªRECORDº on CONSULT-II screen.
5) Check the following.
+ªHO2S1 MNTR (B1)º in ªDATA MONITORº mode changes from
ªRICHº to ªLEANº to ªRICHº 5 times in 10 seconds.
5 times (cycles) are counted as shown below:
R = ªHO2S1 MNTR (B1)º, ªRICHº
L = ªHO2S1 MNTR (B1)º, ªLEANº
+ªHO2S1 (B1)º voltage goes above 0.6V at least once.
+ªHO2S1 (B1)º voltage goes below 0.3V at least once.
+ªHO2S1 (B1)º voltage never exceeds 1.0V.
CAUTION:
+Discard any heated oxygen sensor which has been
dropped from a height of more than 0.5 m (19.7 in) onto a
hard surface such as a concrete floor; use a new one.
+Before installing new oxygen sensor, clean exhaust sys-
tem threads using Oxygen Sensor Thread Cleaner tool
and approved anti-seize lubricant.
DTC P0132 HEATED OXYGEN SENSOR 1 (FRONT) (RICH SHIFT
MONITORING)
SR20DE
Diagnostic Procedure (Cont'd)
EC-727