Saab 9000 - Page 221

218 Fault diagnosis
Poor driveability
1
Conditions
No diagnostic trouble codes.
Diagnostic procedure
0000
0000
0000
0000
OOc=J
· General fault diagnosis rules for poor driveability are
difficult to concretize. However, some hints and ad-
vice are given in the following.
1 Check the engine coolant temperature
Cold starting and warm-up trouble may be caused
by the engine coolant temperature sensor indicating
excessively high engine temperature.
- Connect an ISAT scan tool.
- Contact the Trionic system.
- Select "READ FUNCTIONS".
- Select "COOLANT TEMPERATURE".
- Read off the engine coolant temperature.
- Then contact the EDU.
-Select "READ VALUES".
- Select "COOLANT TEMPERATURE".
- Read off the engine coolant temperature as a
reference.
89°C
EDU
89°C
TRIONIC
The difference between the two temperature read-
ings may be 5~C (9°F) due to tolerances.
Note
If the Trionic system receives no reference ground
on pin 66 ~rom crimped connection J68, it will show
about 20°c (36°F) too high a coolant temperature
even if the temperature sensor is
OK.
Saab9000