Description
The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions, such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan operation, etc.).
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for the other DTC.
| DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition | Possible cause |
| P0506 | ISC SYSTEM (Idle air control system RPM lower than expected) | The idle speed is less than the target idle speed by 100 rpm or more. |
|
DTC CONFIRMATION PROCEDURE
1.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
If the target idle speed is out of the specified value, performEC-140, "Work Procedure", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
>> GO TO 2.
2.PERFORM DTC CONFIRMATION PROCEDURE
Is 1st trip DTC detected? YES >> Proceed to EC-334, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK INTAKE AIR LEAK
Is intake air leak detected? YES >> Discover air leak location and repair.
NO >> Replace ECM. Refer to EC-485, "Removal and Installation".
P0500 VSS
P0507 ISC SystemPower supply and ground circuit
Av control unit
Av control unit : diagnosis procedure
Regarding wiring diagram information, refer to av-331, "wiring diagram".
1.Check fuse
Check that the following fuses are not blown.
Are the fuses blown?
Yes >> replace the blown fuse after repairing the affected circuit. ...
Engine compartment check locations
MRA8DE engine
Engine oil filler cap
Brake and clutch (if so equipped) fluid
reservoir
Air cleaner
Battery
Fuse/fusible link box
Engine coolant reservoir
Radiator cap
Engine oil dipstick
Drive belt location
Windshield-washer fluid reservoir
...
Symptom diagnosis
Multi av system
Symptom table
Related to audio
Related to hands-free phone
Before performing diagnosis, confirm that the cellular phone being used
by the customer is compatible with
the vehicle.
It is possible that a malfunction is occurring due to a version change
of th ...