Sensor Throttle position sensor Description SYSTEM DESCRIPTION Throttle position Input Signal to ECM ECM function Description Actuator NIEC1534 NIEC1534S01 GI MA Ignition switch Crankshaft position sensor (POS) Camshaft position sensor (PHASE) Mass air flow sensor Start signal Engine speed Engine speed and cylinder position Amount of intake air Swirl control valve control Swirl control valve EM LC Engine coolant temperature sensor Engine coolant temperature Swirl control valve position sensor Swirl control valve position Swirl control valve has a valve portion in the intake passage of each cylinder. While idling and during low engine coolant temperature, the swirl control valve closes. Thus the velocity of the air in the intake passage increases, promoting the vaporization of the fuel and producing a swirl in the combustion chamber. Because of this operation, this system tends to increase the burning speed of the gas mixture, improve fuel consumption, and increase the stability in running conditions. Also, except when idling and during low engine coolant temperature, this system opens the swirl control valve. In this condition, this system tends to increase power by improving intake efficiency via reduction of intake flow resistance, intake flow. The swirl control valve is operated by the ECM. Throttle position sensor (Idle position) Engine coolant temperature Swirl control valve OFF Open ON Above 45 C (113 F) Below 44 C (111 F) Open Close FE CL MT AT AX SU BR ST RS BT HA COMPONENT DESCRIPTION NIEC1534S02 Swirl Control Valve NIEC1534S0201 Swirl control valve consists of actuator and valve. The valve is installed in the intake manifold, and the actuator is connected to the rear end of the valve shaft. The swirl control valve uses a step motor which has four winding phases. It operates according to the output pulse signal of the ECM. Two windings are turned ON and OFF in sequence. Each time an ON pulse is issued, the valve opens or closes. When no SC EL IDX SEF407Z EC-1159
Description (Cont d) change in the control position is needed, the ECM does not issue the pulse signal. A certain voltage signal is issued so that the valve remains at that particular opening. Swirl Control Valve Position Sensor NIEC1534S0202 Swirl control valve position sensor is installed on the intake manifold. The sensor is connected to the front end of the valve shaft of the swirl control valve. The sensor responds to the valve shaft movement. This sensor is a kind of potentiometer which transforms the swirl control valve position into output voltage, and emits the voltage signal to the ECM. SEF408Z Specification data are reference values. CONSULT-II Reference Value in Data Monitor Mode NIEC1535 MONITOR ITEM CONDITION SPECIFICATION SWL C/V (B1) Engine speed: Idle Engine coolant temperature is below 44 C (111 F). Engine coolant temperature is above 45 C (113 F). 0-5 step 115-120 step On Board Diagnosis Logic NIEC1536 Malfunction is detected when the target opening angle of swirl control valve controlled by ECM and the input signal from swirl control valve position sensor is not in the normal range. Possible Cause NIEC1537 Harness or connectors (The swirl control valve circuit is open or shorted.) Swirl control valve Harness or connectors (The swirl control valve position sensor circuit is open or shorted.) Swirl control valve position sensor EC-1160
DTC Confirmation Procedure DTC Confirmation Procedure NIEC1538 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. GI MA EM SEF174Y With CONSULT-II 1) Turn ignition switch ON and wait at least 2 seconds. 2) Select DATA MONITOR mode with CONSULT-II. 3) Start engine and let it idle for at least 10 seconds. 4) Turn ignition switch OFF and wait at least 10 seconds. 5) Turn ignition switch ON and wait at least 2 seconds. 6) Start engine and let it idle for at least 10 seconds. 7) Maintain engine speed at about 2,000 rpm for at least 10 seconds. 8) Turn ignition switch OFF, wait at least 10 seconds and then turn ON. If 1st trip DTC is detected, go to Diagnostic Procedure, EC-1163. If 1st trip DTC is not detected, go to next step. 9) Perform step 5 through 8 three times. With GST Follow the procedure With CONSULT-II above. LC FE CL MT AT AX SU BR ST RS BT HA SC EL IDX EC-1161
Wiring Diagram Wiring Diagram =NIEC1539 WEC413 EC-1162 SEF608Z
Diagnostic Procedure 1 CHECK SWIRL CONTROL VALVE POWER SUPPLY CIRCUIT 1. Turn ignition switch OFF. 2. Disconnect swirl control valve harness connector. Diagnostic Procedure NIEC1540 GI MA EM LC 3. Turn ignition switch ON. 4. Check voltage between swirl control valve terminals 2, 5 and ground with CONSULT-II or tester. SEF407Z FE CL MT AT OK GO TO 3. NG GO TO 2. SEF327X AX SU BR 2 DETECT MALFUNCTIONING PART Check the harness for open or short between ECM relay and swirl control valve. Repair harness or connectors. 3 CHECK SWIRL CONTROL VALVE OUTPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 1. Turn ignition switch OFF. 2. disconnect ECM harness connector. 3. Check harness continuity between ECM terminals and swirl control valve terminals as follows. Refer to Wiring Diagram. ST RS BT HA SC MTBL0541 Continuity should exist. 4. Also check harness for short to ground and short to power. OK GO TO 4. NG Repair open circuit or short to ground or short to power in harness or connectors. EL IDX EC-1163
Diagnostic Procedure (Cont d) 4 CHECK SWIRL CONTROL VALVE Check resistance between swirl control valve terminal 2 and terminals 1, 3, terminal 5 and terminals 4, 6. SEF540Z OK GO TO 5. NG Replace intake manifold collector assembly. 5 RETIGHTEN GROUND SCREWS Loosen and retighten engine ground screws. WEC249 GO TO 6. EC-1164
Diagnostic Procedure (Cont d) 6 CHECK SWIRL CONTROL VALVE POSITION SENSOR POWER SUPPLY CIRCUIT 1. Disconnect swirl control valve position sensor harness connector. GI MA EM LC 2. Turn ignition switch ON. 3. Check voltage between swirl control valve position sensor terminal 3 and ground with CONSULT-II or tester. SEF408Z FE CL MT AT OK GO TO 8. NG GO TO 7. SEF306X AX SU 7 DETECT MALFUNCTIONING PART Check the following. Joint connector-2 Harness for open or short between swirl control valve position sensor and ECM Repair harness or connectors. 8 CHECK SWIRL CONTROL VALVE POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 1. Turn ignition switch OFF. 2. Check harness continuity between swirl control valve position sensor terminal 1 and engine ground. Refer to Wiring Diagram. Continuity should exist. 3. Also check harness for short to ground and short to power. OK GO TO 10. NG GO TO 9. 9 DETECT MALFUNCTIONING PART Check the following. Joint connector-3 Harness for open or short between swirl control valve position sensor and TCM Harness for open or short between swirl control valve position sensor and ECM Repair open circuit or short to ground or short to power in harness or connectors. BR ST RS BT HA SC EL IDX EC-1165
Diagnostic Procedure (Cont d) 10 CHECK SWIRL CONTROL VALVE POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 1. Disconnect ECM harness connector. 2. Check harness continuity between ECM terminal 90 and swirl control valve position sensor terminal 2. Refer to Wiring Diagram. Continuity should exist. 3. Also check harness for short to ground and short to power. OK (With CONSULT-II) GO TO 11. NG Repair open circuit or short to ground or short to power in harness or connectors. 11 CHECK INTERMITTENT INCIDENT Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT, EC-838. OK Replace intake manifold assembly. NG Repair or replace. EC-1166