What method is most effective for testing an ignition transformer?

Connecting the ignitor leads together is the most effective method for testing an ignition transformer because it allows the technician to check for proper operation and output directly. When the leads are connected, the transformer should produce a spark, indicating that it is functioning correctly. This method directly assesses the ability of the ignition transformer to generate the necessary voltage to ignite the fuel.

In contrast, using a multimeter may provide readings of resistance or voltage but won't necessarily indicate if the transformer produces a sufficient spark or how it performs under load conditions. Visual inspection can help identify physical damage or signs of wear, but it does not provide an assessment of electrical function. Auditory assessment, while beneficial in some contexts, is subjective and does not reliably measure the performance of the ignition transformer. Thus, connecting the ignitor leads together gives the most direct and informative test of the ignition transformer’s condition.