
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 highAdjusting the position of and opening and closing the air outlets
Front center outlets
Direct air flow to the left or
right, up or down.
Turn the knobs to open or
close the vents.
Turn the knob to open or
close the vent for rear seat
occupants.
М
Direct air flow to the left or right,
up or down.
Open the vent.
Close the vent.
...
If your vehicle overheats
The following may indicate
that your vehicle is overheating.
The engine coolant temperature
gauge shows the red zone or a
loss of engine power is
experienced. (For example,
the vehicle speed does not
increase.)
"Engine Coolant Temp High
Stop in a Safe Place See
Owner's Manual" is shown
on ...
Brake pedal load sensing switch
On-vehicle inspection
Inspect brake pedal load sensing switch
Hint:
Do not remove the brake pedal load sensing switch
from the brake pedal support.
When there is a malfunction in the brake pedal load
sensing switch, replace the brake pedal support.
Disconnect the brake pedal l ...