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".
C1708, C1709, C1710, C1711 Transmitter (no data)
DTC Logic
NOTE:
The Signal Tech II Tool (J-50190) can be used to perform the following
functions. Refer to the Signal Tech II
User Guide for additional information.
Activate and display TPMS transmitter IDs
Display tire pressure reported by the TPMS transmitter
Read TPMS DTCs
Registe ...
Fuel pressure
Work Procedure
FUEL PRESSURE RELEASE
1.FUEL PRESSURE RELEASE
With CONSULT
Turn ignition switch ON.
Perform “FUEL PRESSURE RELEASE” in “WORK SUPPORT” mode of “ENGINE” using
CONSULT
Start engine.
After engine stalls, crank it two or three times to release ...
Tcm branch line circuit
Diagnosis Procedure
1.Check connector
Turn the ignition switch off.
Disconnect the battery cable from the negative terminal.
Check the following terminals and connectors for damage, bend and loose
connection (unit side and connector
side).
TCM
Harness connector f50
Harness co ...