Check voltage between terminal SPD of ECM connector and body ground

Corolla E11 Spd


(a) Remove the ECM with connector still connected (See page SF-62).

(b) Drive the vehicle. CHECK:

Measure voltage between terminal SPD of ECM connector and body ground when the wheel is turned slowly.

Voltage is generated intermittently.


Check and repair harness and connector between combination meter and ECM.




Idle Control System Malfunction


The idle speed is controlled by the Electric Throttle Control System (ETCS).

ETCS is composed of the throttle motor to operate the throttle valve, the magnetic clutch to connect the throttle motor with the throttle valve, the throttle position sensor to detect the opening angle of the throttle valve, the accelerator pedal position sensor to detect the accelerator pedal position, the ECM to control the ETCS and the one valve type throttle body.

The ECM controls the throttle motor to make the throttle valve opening angle properly for the target idle speed.


DTC Detecting Condition

Trouble Area


Idle speed continues to vary greatly from target speed (2 trip detection logic)

• Air induction system

• Electric throttle control system

• PCV piping



Read freeze frame data using TOYOTA hand-held tester or OBD II scan tool. Because freeze frame records the engine conditions when the malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.

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