
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 highLda
(lane departure alert)
Summary of function
While driving on a road that has lane markers, this system recognizes
the lane markers using a camera as a sensor to alert the driver when
the vehicle deviates from its lane.
If the system judges that the vehicle may deviate from its lane, it alerts
the driver using beepin ...
Engine (ignition) switch
(vehicles without smart
key system)
Starting the engine
1. Pull the parking brake switch
to check that the parking
brake is set.
The parking brake indicator will
come on.
2. Check that the shift lever is
set in P.
3. Firmly depress the brake
pedal.
4. Turn the engine switch to
START to start the engine.
â– If the engine does not s ...
Inspection
Inspect cylinder block for warpage
Using a precision straightedge and feeler gauge,
measure the warpage of the surface that is in
contact with the cylinder head gasket.
Maximum warpage:
0.05 Mm (0.0020 In.)
If the warpage is greater than the maximum, replace
the cylinder block ...