Before Changing A Control Module

Experience has shown that the majority of control modules returned for warranty repairs are in perfect working order. In these cases, changing the control module has obviously not cured the fault. Check the following points before changing the control module:
1 Check all grounding points and the power supply for the control module.
2 Using the diagnostic tool, check that all readings are plausible.
3 Using the diagnostic tool, check that all activation commands produce the desired result.
4 If the fault persists, the control module must be changed.
5 It is important to ground yourself, by touching the engine for example, before handling a control module. Never touch the control module pins.