Body and Frame: Testing and Inspection

General Fault Diagnosis In Electronic Systems

Control module

When the control module is supplied with current, the processor in it is tripped. The processor then reads the instructions stored in the control module's memory.

The control module is programmed to read the inputs and activate the outputs. If the control module program is faulty, the diagnostic trouble code "Internal Control Module Fault" will be generated.

The control module must be supplied with current before the system will function. The control module is supplied with current and the processor tripped when the control module can be contacted by the diagnostics instrument.

Outputs

The purpose of the system is to control a number of functions by means of various actuators, such as an injector or 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 proper power supply or ground connection.

Inputs

A condition for the control module's capability of controlling its actuators is that the system's sensors supply it with correct values.

Sensor performance can be checked with the diagnostics instrument.