900 Turbo Convertible L4-1985cc 2.0L DOHC Turbo EFI (1994)
OPERATION
Engine Control Module
Saab Trionic principally controls:
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Ignition (by means of the ignition discharge module),
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Fuel injection (which is sequential),
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Boost pressure (by means of a solenoid valve).
The Trionic engine control module has a 70-pole terminal and is located at the right-hand A-pillar. When the powertrain is removed, the ECM
terminal and its wiring are guided out through the bulkhead partition.
The ECM has a 32-bit processor which can perform 2 million calculations per second.
A number of sensors supply information to the ECM, which processes these using matrices which have been stored in the ECM after engine
operation has been optimized. Examples of such important matrices are ignition timing matrices, fuel matrices and boost pressure matrices.
The ECM is programmed for the B204L and is only to be used for this engine in the Saab 900.
The ECM may be damaged by electrostatic discharges or shorting of any of the ECM's outputs, and great care must therefore be taken whenever
handling the ECM, for example in fault diagnosis, e.g. with a break out box.
