
Description
The ecm continuously monitors its own internal memory status, internal circuits, and output signals transmitted to the throttle actuator. This self-check ensures that the ecm is functioning properly. If any malfunction is detected, the ecm sets the appropriate dtc and illuminates the mil.
The ecm memory status is diagnosed by internal mirroring of the main cpu and the sub cpu to detect random access memory (ram) errors. The two cpus also perform continuous mutual monitoring. The ecm illuminates the mil and sets a dtc if: 1) outputs from the two cpus are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ecm malfunction is found.

Monitor strategy

Typical enabling conditions
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Typical malfunction thresholds


Inspection procedure
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

System voltage
Starter relay circuit highLubrication system
On-vehicle inspection
Check engine oil level
Warm up the engine, stop the engine and wait for 5
minutes.
Check that the engine oil level is between the l and
f marks of the oil dipstick.
If low, check for leakage and add oil up to the f
mark.
Notice:
Do not add engine oil a ...
Throttle actuator control system
Description
The throttle actuator is operated by the ecm, and opens and closes the
throttle valve using gears. The
opening angle of the throttle valve is detected by the throttle position (tp)
sensor, which is mounted on
the throttle body. The tp sensor provides feedback to the ecm in ord ...
Vin not programmed or mismatch - ecm / pcm
Description
Dtc p0630 is set when the vehicle identification number (vin) is not stored
in the engine control module
(ecm) or the input vin is incorrect. Input the vin with the intelligent tester.
Monitor strategy
Typical enabling conditions
Typical malfunction thresholds
Com ...