Ford TFI-IV / DI Ignition Coil Primary Resistance Test Diagram

This document is a single illustrated figure (numbered 7.10) from an automotive service manual showing how to measure the primary resistance of an ignition coil used with TFI-IV (Thick Film Integrated) or DI (Distributor Ignition) systems. The line drawing depicts an E-core style ignition coil with its high-tension tower and a two-terminal primary connector. Two test probes from an analog ohmmeter (identified by the Ω symbol on the meter face) are inserted into the coil's primary connector terminals, one of which is marked "+". The illustration demonstrates the proper probe placement for checking primary winding resistance. This figure is part of a set of ignition-system test procedure scans (companion images cover initial diagnosis, secondary resistance, and supply voltage testing for the same TFI coil). The document contains no resistance specifications, year/model applicability, or step-by-step text — it is purely a visual reference for where to connect the ohmmeter leads when performing the primary resistance test on a TFI-IV or DI ignition coil, such as those used on Ford trucks like the uploader's 1990 Bronco.