
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 highReassembly
Install generator rotor assembly
Install the washer onto the generator rectifier end
frame.
Install the generator rotor onto the generator
rectifier end frame.
Using a 32 mm socket wrench and press, slowly
push the generator drive end frame onto the
generator ...
On-vehicle inspection
Check throttle body
Check the throttle control motor operating sounds.
Turn the ignition switch on.
When pressing the accelerator pedal, check
the operating sound of the running motor. Make
sure that no friction noises emit from the motor.
If friction noise exists, replace t ...
Valve body
Components
Disassembly
Remove shift solenoid valve slt
Remove the bolt, plate and shift solenoid valve slt
from the valve body.
Remove shift solenoid valve sl1
Remove the bolt, plate and shift solenoid valve sl1
from the valve body.
Remove shift solenoid ...