b.
The lower voltage must be below 1V and the upper must be battery voltage.
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 ECM controls both coils by grounding their control circuits. According to the control signals from the ECM, the valve rotor rotates to control the by pass airflow into the engine.
The ECM sets DTC P0506 if the difference to the target idle engine speed is lower than the predetermined threshold value.
Item | Detecting Condition | Possible cause |
Monitoring Strategy | ● Open in power line ● Open in control line ● Short in control line ● faulty ISCA ● Faulty ECM | |
Threshold value | ● Shorted to GND or disconnected | |
Enable Conditions | ||
Diagnostic Time | ● Continuous | |
MIL on condition |
A/CON switch OFF : 25~45%
A/CON switch ON : 35~55%
Using the channel 1,2 of scan tool,it is the waveform at terminal 1,3 of ISCA in idle.
The wave must be opposite to each other.
The lower voltage must be below 1V and the upper must be battery voltage.
Using the channel 1,2 of scan tool,it is the waveform at terminal 1,3 of ISCA in idle.
The wave must be opposite to each other.
The lower voltage must be below 1V and the upper must be battery voltage.
If the waveform changes as TPS changes or as A/CON switch on and off,it is normal.
In case there is no symptom and wrong data but DTC is shown
The problem may be intermittent so slightly shake the connector and harness vertically and horizontally to check if there is any data changes
If the data changes normally, the problem was intermittent so erase DTC and verify the same DTC reoccure.
Go to "Terminal and Connector inspection"
In case there is symptom and wrong data with DTC
Check open,short or connector’s connection for ISCA.
Check the deterioration of ISCA performance.
Go to "Signal circuit inspection"
