Page 1289 of 3051

CONSULT-II Reference Value in Data Monitor
Mode
NLEC1580
MONITOR ITEM CONDITION SPECIFICATION
IACV-AAC/V+Engine: After warming up
+Air conditioner switch: OFF
+Shift lever: ªNº
+No-loadIdle 5 - 20 steps
2,000 rpm Ð
ECM Terminals and Reference ValueNLEC1581Specification 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.
TER-
MINAL
NO.WIRE
COLORITEM CONDITION DATA (DC Voltage)
6
7
15
16BR
LG
GY/L
ORIACV-AAC valve[Engine is running]
+Warm-up condition
+Idle speed0.1 - 14V
On Board Diagnosis LogicNLEC1582
DTC No. Malfunction is detected when ... Check Items (Possible Cause)
P0505+An improper voltage signal is sent to ECM through the
valve.+Harness or connectors
(The IACV-AAC valve circuit is open.)
+IACV-AAC valve
SEF058Y
DTC Confirmation ProcedureNLEC1583NOTE:
+If ªDTC Confirmation Procedureº has been previously
conducted, always turn ignition switch ªOFFº and wait at least
10 seconds before conducting the next test.
+If the target idle speed is out of the specified value, per-
form ªIdle Air Volume Learningº, EC-581, before conduct-
ing ªDTC Confirmation Procedureº. For the target idle
speed, refer to ªService Data and Specifications (SDS)º,
EC-1062.
With CONSULT-II
1) Turn ignition switch ªONº.
2) Select ªDATA MONITORº mode with CONSULT-II.
3) Start engine and warm it up to normal operating temperature.
4) Rev engine from idle to 2,000 rpm 20 times.
If 1st trip DTC is detected, go to ªDIAGNOSTIC
PROCEDUREº, EC-867.
With GST
Follow the procedure ªWith CONSULT-IIº above.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
CONSULT-II Reference Value in Data Monitor Mode
EC-864
Page 1290 of 3051
Wiring DiagramNLEC1584MODELS WITH ECM IN ENGINE COMPARTMENTNLEC1584S01
YEC704
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Wiring Diagram
EC-865
Page 1291 of 3051
MODELS WITH ECM IN CABINNLEC1584S02
YEC925
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Wiring Diagram (Cont'd)
EC-866
Page 1292 of 3051

Diagnostic ProcedureNLEC1585
1 CHECK POWER SUPPLY
1. Turn ignition switch ªOFFº.
2. Disconnect IACV-AAC valve harness connector.
SEF221X
3. Turn ignition switch ªONº.
4. Check voltage between terminal 2, 5 and ground with CONSULT-II or tester.
SEF343X
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 DETECT MALFUNCTIONING PART
Check the following.
+15A fuse
+Harness connectors E76, F36
+ECM relay
+Harness for open or short between IACV-AAC and fuse
©Repair harness or connectors.
3 CHECK OUTPUT SIGNAL CIRCUIT
1. Turn ignition switch ªOFFº.
2. Disconnect ECM harness connector.
3. Check harness continuity between
ECM terminal 6 and IACV-AAC valve terminal 1,
ECM terminal 7 and IACV-AAC valve terminal 4,
ECM terminal 15 and IACV-AAC valve terminal 3,
ECM terminal 16 and IACV-AAC valve terminal 6.
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©Repair open circuit or short to ground or short to power in harness or connectors.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Diagnostic Procedure
EC-867
Page 1293 of 3051
4 CHECK AIR CONTROL VALVE (POWER STEERING) OPERATION-I
1. Reconnect the ECM harness connector and IACV-AAC valve harness connector.
2. Disconnect the vacuum hose connected to the air control valve (Power steering) at intake air duct.
3. Start engine and let it idle.
4. Check vacuum hose for vacuum existence.
SEF778Z
Vacuum does not exist or slightly exist.
OK or NG
OK©GO TO 5.
NG©Replace air control valve (Power steering).
5 CHECK AIR CONTROL VALVE (POWER STEERING) OPERATION-II
Check the vacuum hose for vacuum existence when steering wheel is turned.
SEF778Z
Vacuum should exist.
OK or NG
OK©GO TO 8.
NG©GO TO 6.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Diagnostic Procedure (Cont'd)
EC-868
Page 1294 of 3051
6 CHECK VACUUM PORT
1. Stop engine.
2. Disconnect the vacuum hose connected to the air control valve (Power steering) at the vacuum port.
3. Blow air into vacuum port.
4. Check that air flows freely.
SEF779Z
OK or NG
OK©GO TO 7.
NG©Repair or clean vacuum port.
7 CHECK VACUUM HOSES AND TUBES
1. Disconnect vacuum hoses between the air control valve (Power steering) and vacuum port, air control valve (Power
steering) and air duct.
2. Check hoses and tubes for cracks, clogging, improper connection or disconnection.
SEF109L
OK or NG
OK©GO TO 8.
NG©Repair hoses or tubes.
8 CHECK IACV-AAC VALVE
Refer to ªComponent Inspectionº, EC-871.
OK or NG
OK©GO TO 10.
NG©GO TO 9.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Diagnostic Procedure (Cont'd)
EC-869
Page 1295 of 3051

9 REPLACE IACV-AAC VALVE
1. Replace IACV-AAC valve assembly.
2. Perform ªIdle Air Volume Learningº, EC-581.
Is the result CMPLT or INCMP?
CMPLT or INCMP
CMPLT©INSPECTION END
INCMP©Follow the construction of ªIdle Air Volume Learningº.
10 CHECK TARGET IDLE SPEED
1. Turn ignition switch ªOFFº.
2. Reconnect all harness connectors and vacuum hoses.
3. Start engine and warm it up to normal operating temperature.
4. Also warm up transmission to normal operating temperature.
+For models with CONSULT-II, drive vehicle until ªFLUID TEMP SEº in ªDATA MONITORº mode of ªCVTº system indi-
cates less than 0.9V.
+For models without CONSULT-II, drive vehicle for 10 minutes.
5. Stop vehicle with engine running.
6. Check target idle speed.
750±50 rpm
OK or NG
OK©GO TO 11.
NG©Perform ªIdle Air Volume Learningº, EC-581.
11 CHECK INTERMITTENT INCIDENT
Perform ªTROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENTº, EC-670.
©INSPECTION END
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Diagnostic Procedure (Cont'd)
EC-870
Page 1296 of 3051
SEF605Y
SEF089X
Component InspectionNLEC1586IACV-AAC VALVENLEC1586S011) Disconnect IACV-AAC valve harness connector.
2) Check IACV-AAC valve resistance.
Condition Resistance
Terminal 2 and terminals 1, 3
20-24W[at 20ÉC (68ÉF)]
Terminal 5 and terminals 4, 6
3) Reconnect IACV-AAC valve harness connector.
4) Remove idle air adjusting unit assembly (IACV-AAC valve is
built-in) from throttle body.
(The IACV-AAC valve harness connector should remain con-
nected.)
5) Turn ignition switch ªONº and ªOFFº, and ensure the IACV-
AAC valve shaft smoothly moves forward and backward,
according to the ignition switch position.
If NG, replace the IACV-AAC valve.
DTC P0505 IDLE AIR CONTROL VALVE (IACV) Ð AUXILIARY AIR CONTROL
(AAC) VALVE
SR20DE
Component Inspection
EC-871