TB8100 Service Manual Power Management Unit Fault Finding 215© Tait Electronics Limited September 200613 Power Management Unit Fault FindingThis chapter provides enough fault finding information to allow you to tracethe fault to an individual board or card in the PMU. It does not provide anyinformation to allow fault finding down to component level. If the fault istraced to the auxiliary power supply board or a plug-in card, the standardprocedure is to discard the faulty item and fit a new one. However, if thefault is traced to the DC converter board or AC converter board, you mustreplace the complete DC or AC module.The fault finding procedures provided in this chapter assume you are familiarwith the operation of the TB8100 Service Kit and Calibration Kit.Figure 13.1 on page 218 identifies the individual boards and cards, andshows how they are configured in an AC and DC PMU. “Identifying thePMU” on page 217 explains how to identify the model and hardwareconfiguration of a PMU from its product code.Note For the sake of simplicity and clarity, the instructions and illustra-tions in this chapter refer to an AC and 12V DC PMU fitted withan auxiliary power supply board. However, the same basic proce-dures and techniques apply to other models of PMU.
