Saab 9000 - Page 90

Driving a trip
Fault diagnosis described in the service manual al-
.
ways ends with a final check.
The final check includes a driving cycle that is specif-
ic for each type of rectified fault.
The driving cycle ensures that On-Board Diagnostic
II is performed for the function in question.
Any remaining fault will subsequently be revealed on
DTC readout.
After
an
individual
fault has been rectified, a check is
made in this way to confirm that the fault really has
qeen rectified.
A trip entails driving in such a way that all compo-
nents and functions embraced by On-Board Diag-
nostic U
are
monitored.
After a very extensive repair involving a large number
of emission-related components or functions, such
as when the power train has been removed, a trip
may well be warranted. Any faults can be revealed
afterwards by requesting a DTC readout.
When a trip has been made, all conditions for On-
Board Diagnostic II have been fulfilled one by one in
the right order.
Technical Description 87
The time it takes to complete a trip will mainly depend
on the following factors:
• traffic conditions
• driving style
• engine management system version
• any faults detected
• climate (affects A/C and radiator fan engagement,
which may disturb a particular diagnosis)
Since the various possible
combinations of
the
above factors are infinite in number, the time it takes
to complete a trip may vary
widely.
The
fdllowing ex-
ample of a trip is therefore only valid if the following
conditions are fulfilled:
• choice of traffic conditions according to driving pro-
file
• driving according to driving profile
• Trionic M96-
• A/C disengaged and radiator fan eng_aged
contmu-
ously
for a certain time
• only
1
fault
can be detected with certainty.
Saab 9000
I