- Sub-throttle servo motor operation Out of specification → Replace.
a. Check whether or not the sub-throttle valve is seized.
- 1. Turn the nut of worm shaft of the subthrottle servo motor by hand to check that the sub-throttle valve is moved smoothly by hand.
- 2. If it is not moved smoothly, disconnect the link between the sub-throttle servo motor and sub-throttle valve, and then check whether or not the sub-throttle valve is moved smoothly by hand. Refer to «Throttle bodies».
- 3. When the sub-throttle valve is not moved smoothly, repair or replace it since the cause is the seizure of subthrottle valve body itself. When it moved smoothly at Step (1) and (2), replace the sub-throttle servo motor.
b. Perform the self-diagnosis mode and check the operation of sub-throttle valve by visual inspection (Code No: 56).
The operation should be carried out as 5-second drive in the full open direction, 2-second stop and 5-second drive in the full close direction.