FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Before Changing a Control Module










Before Changing a Control Module

Experience has shown us that most control modules returned for repairs under warranty have been free from faults. In these cases changing the control module has not rectified the fault. Perform therefore the following steps before changing a control module:
1 Check all grounding points and the power supply to the control module.
2 Check with a diagnostics tool that all test values are reasonable.
3 Check with a diagnostics tool that all functions are operating.
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.