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 reasonable (several readings can affect a function).
3 Using the diagnostic tool, check that all activations function. (A fault in one output circuit can affect another output circuit).
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.