P0507
DTC P0507 IDLE AIR CONTROL SYSTEM-RPM HIGHER THAN EXPECTEDComponent Location:
COMPONENT LOCATION
GENERAL DESCRIPTION
The Idle Speed Control Actuator (ISCA) is installed on the intake manifold and controls the intake airflow that is bypassed around the throttle plate to keep constant engine speed when the throttle valve is closed. The function of the ISCA is to maintain idle speed according to various engine loads and conditions, and also to provide additional air during starting. The ISCA consists of an opening coil, a closing coil, and a permanent magnet. Based on information from various sensors, the PCM controls both coils by grounding their control circuits. According to the control signals from the PCM, the valve rotor rotates to control the by pass airflow into the engine.
DTC DESCRIPTION
It the actual engine speed is higher than the target engine speed at idle, the PCM determines that a fault exists and a DTC is stored.
DTC Detecting Condition:
Schematic Diagram:
MONITOR SCANTOOL DATA
1. Ignition "OFF"
2. Connect Scantool and Engine "ON"
3. Monitor ISC ACTUATOR DUTY parameter on scantool.
4. Is the ISC ACTUATOR DUTY parameter within specification?
YES: Fault is intermittent caused by poor contact in Fuel Level Sensor's and/or PCM's connector or was repaired and PCM memory was not cleared. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to "W/Harness Inspection" procedure.
TERMINAL & CONNECTOR INSPECTION
1. Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?
YES: Repair as necessary and go to "Verification of Vehicle Repair" procedure.
NO: Go to" Power Circuit Inspection "procedure.
POWER SUPPLY CIRCUIT INSPECTION
1. Check Voltage
1. Ignition "OFF"
2. Disconnect ISC Actuator connector.
3. Ignition "ON" & Engine "OFF"
4. Measure voltage between terminal 2 of ISCA harness connector and chassis ground.
Specification: Approx. 12 V
5. Is the measured voltage within specifications?
YES: Go to "Control Circuit Inspection" procedure.
NO:
- Check for open in harness.
- Check whether EGR fuse 15 A is installed or blown off.
- Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.
CONTROL CIRCUIT INSPECTION
1. Check for short to battery in harness
1. Ignition "OFF"
2. Disconnect ISC Actuator connector.
3. Measure resistance between terminal 2 of ICs harness connector and terminal 1 of harness connector.
4. Measure resistance between terminal 2 of ICs harness connector and terminal 3 of harness connector.
Specification: Infinite
5. Is the measured resistance within specifications?
YES: Go to Check for "short to ground in harness" as below.
NO:
- Check for short to battery in harness.
- Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.
2. Check for short to ground in harness
1. Ignition "OFF"
2. Disconnect ISCA sensor connector.
3. Measure resistance between terminal 1 of harness connector and chassis ground.
4. Measure resistance between terminal 3 of harness connector and chassis ground.
5. Is the measured resistance within specifications?
YES: Go to " Check for open in harness " as below.
NO:
- Check for short to battery in harness.
- Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.
3. Check for open in harness
1. Ignition "OFF"
2. Disconnect ISCA sensor connector.
3. Measure resistance between terminal 1 of ISCA harness connector and terminal 28 of PCM harness connector.
4. Measure resistance between terminal 2 of ISCA harness connector and terminal 14 of PCM harness connector.
Specification: Below 1 Ohms
5. Is the measured resistance within specifications?
YES: Go to" Component Inspection "procedure.
NO:
- Check for open in harness.
- Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.
SYSTEM INSPECTION
1. Air Leakage Inspection
1. Visually/physically inspect the air leakage in intake/exhaust system as following items.
1. If OK, go to next step.
2. If NG, repair as necessary and go to "Verification vehicle Repair" procedure.
- Vacuum hoses for splits, kinks and improper connections.
- Throttle body gasket.
- Gasket between intake manifold and cylinder head.
- Seals between intake manifold and fuel injectors.
- Exhaust system between HO2S and Three way catalyst for air leakage.
2. Check for air leakage in EVAP Purge control valve.
1. Remove the manifold side vacuum hose from the EVAP canister purge valve.
2. Using a hand vacuum pump apply specified vacuum(Approx. 15 in, Hg) to the manifold side of the valve.
3. Does the valve hold vacuum?
YES: Go to "Component Inspection" procedure.
NO: Repair air leakage and go to "Verification Vehicle Repair" procedure.
COMPONENT INSPECTION
1. Check Accelerator Cable
1. Ignition "OFF" & Engine "OFF"
2. Check free play of accelerator Cable.
[Specification] 1.0 - 3.0 mm(0.04 - 0.12 in)
3. Is the free play within specifications?
YES: Go to " Check TPS " as below.
NO: Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure.
2. Check TPS
1. Ignition "OFF"
2. Install Scantool then, Ignition "ON" & Engine "OFF"
3. Monitor "TPS VALUE" parameter on CURRENT DATA.
Specification:
Throttle valve fully closed: Approx. 0.2 - 0.8 V.
Throttle valve fully open: Approx. 4.0 - 4.4 V.
TP sensor signal should increase smoothly as throttle is opened.
4. Is the Current data displayed correctly?
YES: Go to "Check PCSV" as below.
NO: Repair or replace as necessary and then, go to "Verification of Vehicle Repair procedure.
3. Check PCSV
1. Ignition "OFF"
2. Disconnect PCSV connector.
3. Disconnect the hose leading from the PCSV to the intake manifold at PCSV.
4. Apply a vacuum at the nipple and verify that the PCSV holds vacuum.
5. Ignition "ON" & Engine OFF"
6. Ground terminal 2 of the PCSV connector (should hear a faint click from PCSV).
7. Vacuum should be released.
8. Repeat this procedure 4 or 5 times to ensure PCSV reliability.
9. Is PCSV working properly?
YES: Go to "Check ISCA "as below.
NO: Repair or replace as necessary and then, go to "Verification of Vehicle Repair" procedure
4. Check ISCA
1. Ignition "OFF"
2. Disconnect ISCA connector.
3. Measure resistance between terminals 3 and 2 of the ISCA connector. (To component Side).
4. Measure resistance between terminals 2 and 1 of the ISCA connector. (To component Side).
[Specification]
Terminal 3 and 2 Approx. 10.5 - 14 Ohms [20 °C (68 °F)]
Terminal 2 and 1 Approx. 10 - 12.5 Ohms [20 °C (65 °F)]
5. Is the measured resistance within specifications?
YES:
- Substitute with a known - good PCM and check for proper operation.
- If the problem is corrected, replace PCM and go to "Verification of Vehicle Repair" procedure.
NO:
- Substitute with a known - good ISCA and check for proper operation.
- If the problem is corrected, replace ISCA and go to "Verification of Vehicle Repair" procedure.
VERIFICATION OF VEHICLE REPAIR
After a repair, it is essential to verify that the fault has been corrected.
1. Monitor and record the Freeze Frame Data for the Diagnostic Trouble Code(DTC) which has been diagnosed.
2. Using a Scantool, Clear the DTCs.
3. Operate the vehicle within conditions noted in the freeze frame data or enable conditions.
4. Monitor that all readiness tests have been verified as " Complete"
5. Are any DTCs present?
YES: Go to the applicable troubleshooting procedure.
NO: System is performing to specification at this time.