Ignition Coil Resistance (Internally Mounted)
- Turn ignition off. Remove the distributor cap and coil assembly. Turn cap upside down. See Fig 1
. Set ohmmeter to low scale. Connect leads to coil BAT and TACH terminals. If resistance is more than zero, replace ignition coil.
- Set ohmmeter on high scale. Connect one lead to coil secondary terminal and other lead first to TACH terminal and then to ground terminal. If resistance reading in BOTH instances is infinite, replace ignition coil.
Courtesy of GENERAL MOTORS CORP.