Fault codes
Dds: exvl diagnosis -> position error, potentiometer, short circuit to ground or open circuit (s.C. Gnd or c.O.), Potentiometer short circuited to vdc (potentiometer s.C vdc).
Dashboard: the error "exvl" (exhaust bypass valve) is shown on the service display. The eobd warning light activates.
Wiring diagram
M exhaust bypass valve motor with potentiometer s for position detection, bbs bbs unit connection. 10 Bbs black/blue - bk/b, 15 bbs brown/red - bn/r, 4 bbs yellow/blue - y/b, 18 bbs black/orange - bk/o, 19 bbs black/white - bk/w.
Location of connections and components
Exhaust bypass valve connection.
The image shows the exhaust system. The oxygen sensor for the horizontal cylinder (1) is visible on the right, the oxygen sensor for the vertical cylinder (2) is on the left. The catalytic converter is contained within the silencer, while the by-pass valve is installed in the section of pipe connecting the silencer to the twin tailpipes. A metal cable, controlled by an actuator with electric motor and a position sensor, branches off from the exhaust bypass valve.
Pin numbering of wiring harness side bbs unit connection
Crankcase halves
Bearing
Bearing holder bushing
Alternator-side crankcase half
Bearing
Circlip
Washer
Bearing
Sealing ring
Bearing
Retaining plate
Screw
Screw
Clutch-side crankcase half
Sealing ring
Bearing
Circlip
Bearing holder bushing
Bearing
Plug
Screw
Spacer
Bush ...
Removal of the intake manifold and coolant union
Loosen the clips (f) and remove the hoses (t).
Remove the manifolds (25) undoing the screws (21).
Loosen the clamp (a) and remove the hose (b). Remove the union (12) and
recover the seal (24).
...
Residual range indication when the service is due
After resetting the first oil service warning (triggered at
1000 km), upon every key-on the system displays the
indication of which type of service should be performed next
(oil service or desmo service) and the residual range.
A (green) warning (1, fig. 32) Is activated for 2 seconds on
ever ...