P0505

DTC P0505 IDLE AIR CONTROL SYSTEM MALFUNCTION





SYSTEM DIAGRAM





WIRING DIAGRAM






DETECTING CONDITION





DTC CONFIRMATION PROCEDURE

NOTE: Check to make sure that following conditions are satisfied when using this DTC CONFIRMATION PROCEDURE.
- Intake air temp.: between -14°C and 70°C (6.8°F and 158°F)
- Atmospheric pressure: higher than 540 mmHg (Altitude: lower than 2,790 m (9,150 ft))
- Electric load switch, A/C switch, power steering pressure switch and starter switch: all turned OFF.





TROUBLESHOOTING

Idle Air Adjusting Screw and Its Passage Check





Using SUZUKI scan tool
1) Connect SUZUKI scan tool to DLC with ignition switch OFF.
2) Warm up engine to normal operating temperature and keep it at idle speed.
3) Check that "IAC DUTY" value displayed on SUZUKI scan tool increases when idle air adjusting screw is tightened and reduces when loosened.
If check result is as described above, idle air adjusting screw and its passage are in good condition.
If not, idle air adjusting screw is faulty or air passage is clogged.





Not using SUZUKI scan tool
1) Using service wire, ground diagnosis switch terminal in monitor coupler and connect duty meter (or volt meter) between duty output terminal and ground terminal of monitor coupler.
2) Warm up engine to normal operating temperature and keep it running at idle speed.
3) Check that idle air control duty value indicated by duty meter (or volt meter) increases when idle air adjusting screw is tightened and reduces when loosened.
If check result is as described above, idle air adjusting screw and its passage are in good condition.
If not, idle air adjusting screw is faulty or air passage is clogged.





Fast Idle Plunger Operation Check
1) Measure plunger protrusion "a" when engine coolant temp. is 25°C (77°F).
"a" = 26.6 - 27.4 mm (1.048 - 1.078 in.)

2) Warm up engine and check to make sure that fast control cam is off cam follower lever at engine coolant temp. of 52 - 68°C (126 - 154°F)

IAC Valve And Its Circuit Check





1) Turn ignition switch OFF and disconnect ECM connectors from ECM.
2) Check for proper connection to ECM at E33-24 (E175-28) and E34-11 (E172-8) terminals.
3) If OK, check resistance between E33-24 (E175-28) and E34-11 (E172-8) terminals of ECM connectors.

Resistance: 11 - 14 Ohms at 20°C, 68°F

4) Check resistance between E33-24 (E175-28) terminal of ECM connector and body ground.

Resistance: Infinity (No continuity)

If check result in above steps 3) and 4) are as specified, proceed step 7).
If circuit open or short is found, proceed step 5).





5) Disconnect IAC valve coupler.
6) Check AC valve for resistance.

Resistance between two terminals: 11 - 14 Ohms at 20°C, 68°F

Resistance between terminal and valve body: Infinity (no continuity)

If check results are not as specified,.replace IAC valve. If IAC valve is in good condition, check wire harnesses for open and short to ground.





7) Connect ECM connectors with ignition switch OFF.
8) Start engine and check engine idle speed.





9) Connect 12V battery to IAC valve terminals as shown figure with engine running and check engine idle speed.

CAUTION: Wrong connection cause IAC valve to burn, connect each wire to correct terminal.

10) Engine idle speed observed step 9) should be higher than engine idle speed observed step 8).
If check result is not as specified, replace IAC valve.