DI/APC Control Module

Before replacing a control module





When all checks have been carried out in accordance with the diagnostic procedures programme for the diagnostic trouble code concerned or through manual fault diagnosis without any fault having been found, it is natural to assume that the control module is at fault.

Carefully go through the following points before finally pinpointing the DI/APC control module as the cause of the fault.

1 Check once again that every single point in the diagnostic procedure for the relevant diagnostic trouble code has been carried out correctly and conscientiously.

2 Study the wiring diagram of the circuit concerned and make sure you understand how it works. Relevant parts of the technical description and description of operation, as well as Service Manual 3:2 "Electrical system, wiring diagrams", may be of assistance in this respect.

3 When removing and/or fitting the control module, bear in mind that it is sensitive to electrostatic discharges, see page 131.

4 Check the control module's power supply and all grounding points once more.

5 Our experience indicates that 80% of all control modules returned in connection with repairs carried out under warranty are in perfect working order. Be restrictive with control module replacement. Give careful thought to all possible causes of a fault before changing the control module.

6 If the original fault still persists, the control module will have to be changed.