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
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.
Disassembly
Remove radiator grille sub-assembly
Remove the 4 bolts and 4 nuts.
Detach the 6 claws and remove the radiator grille.
Remove no. 1 Radiator grille lower
Detach the 18 claws and remove the radiator grille.
Remove no. 2 Radiator grille lower
Detac ...
Customization
Customizable features
Your vehicle includes a variety of electronic features that can be
personalized to your preferences. The settings of these features
can be changed by using the steering wheel switches, entune
premium audio with navigation or entune audio, or at your
toyota dealer.
Customi ...
Air inlet control servo motor
Components
Removal
Remove blower assembly
Remove the blower (see page ac-203).
Remove air inlet control servo motor (see
page ac-210)
Inspection
Inspect air inlet control servo motor (for automatic air conditioning
system)
Inspect the servo motor operation. ...