The excs is operated by the signal supplied from the ecm. The open/close operation of the excv is performed by the excva which is controlled by the ecm by changing the current direction of the actuator motor. The position sensor (incorporated in the excva) detects the excva movement by measuring the voltage and then the ecm determines the excv opening angle based on the engine rpm and gear positions. Every time the ignition switch is turned on, the excva automatically drives the excv and detects full close/open position voltages and sets the excv to middle position.
Full close

Full open

Exhaust control system descriptionUsing the testers
Incorrectly connecting the (+) and (.) Probes may
cause the inside of the tester to be burned.
If the voltage and current are not known, make
measurements using the highest range.
When measuring the resistance with the multi-circuit
tester (1), ∞ will be shown as 10.00 ...
Ignition coil and spark plug removal and
installation
Removal
The hot
engine can burn you.
Wait until the engine is cool enough to touch.
Turn the ignition switch off.
Remove the air cleaner box. Refer to “air cleaner box removal and
installation” in section 1d .
Disconnect the lead wire couplers (1).
...
Drive chain cleaning and lubricating
Clean and lubricate drive chain
every 1 000 km (600 miles)
Clean and lubricate the drive chain in the following
procedures:
clean the drive chain with kerosine. If the drive chain
tends to rust quickly, the intervals must be
shortened.
Caution
do not use trichloroethyle ...