9-3 Coupe (9400) L4-2.0L Turbo (B204) (1999)
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a
Search in EPSI during fault diagnosis in the system where the trouble exists.
b
If the symptom description for the system in question matches the complaint, it is likely that the correct fault diagnosis description has been
found.
Repair according to instructions.
7
If there is no match with regards to diagnostic trouble codes or symptoms, the technician must perform a fault diagnosis himself.
A final check must be performed after the repair is completed.
Good technical knowledge of the product is required to solve this type of problem.
8
The work on the car is finished.
General information about fault diagnosis in electronic systems
Control modules
When the control module is supplied with current, the processor is activated. The processor then reads instructions that are stored in the control module
memory.
The control module is programmed to read off inputs and activate the outputs. If the control module programming is defective, the diagnostic trouble
code "Internal control module fault" is generated.
The control module must be supplied with current for the system to function. The control module is supplied with current and the processor is activated
if the control module can be contacted by the diagnostics tool.
Outputs
The purpose of the system is to control a number of functions by means of various actuators, e.g. an injector or a lamp. For the system to be capable of
performing its functions, it must be possible to activate the actuators. For this reason, the actuators must be connected to the control module and have a
correct power supply or ground connection.
Inputs
A condition for the control module to be able to control its actuators is that the system sensors transmit the correct information to the control module.
The function of the sensors can be checked using the diagnostics tool.
