Vitara 2.0L & Grand Vitara 2.5L

Disconnect harness connector from ignition coil. Remove ignition coil from valve cover. Using DVOM, measure resistance between terminals of ignition coil (primary resistance). See Fig 1 .
Using a 12-volt battery and an ammeter, measure secondary coil current. See Fig 2 . See IGNITION COIL RESISTANCE table. Ensure current does not flow with polarities reversed. Repeat for remaining ignition coils. Replace ignition coils if resistance or current is not as specified.

Fig 1: Measuring Primary Coil Resistance (Vitara 2.0L & Grand Vitara 2.5L)
Courtesy of SUZUKI OF AMERICA CORP.

Fig 2: Measuring Secondary Coil Current (Vitara 2.0L & Grand Vitara 2.5L)
Courtesy of SUZUKI OF AMERICA CORP.