Initial Inspection and Diagnostic Overview

Before Changing A Control Module

It has been found that the majority of control modules returned for repair under warranty are in perfect working order. In these cases, fitting a replacement control module has obviously not cured the fault. Therefore, go through the following points carefully before definitely deciding to change the control module:




1. Check all grounding points and the power supply for the control module.
2. Use the diagnostics instrument to check that all test readings obtained are plausible. (Several test readings may have a bearing on a particular function).
3. Use the diagnostics instrument to check that all activated functions are in working order. (A fault in one output circuit could affect another output circuit).




4. If the fault persists the control module will have to be changed.
5. When handling control modules it is important to ground yourself first by touching the bonnet, for instance.
Avoid touching the control module's pins