Ignition Coil Resistance

Remove primary and secondary leads from ignition coil. Using ohmmeter, check primary resistance between positive and negative terminals of coil. See Fig 1 . Resistance should be as specified in IGNITION COIL RESISTANCE table. If resistance is not as specified, replace ignition coil.
Check secondary resistance between coil towers of each coil. See Fig 2 . On leading coil of RX7, check secondary resistance between both high tension towers. On trailing coil of RX7, check secondary resistance between terminal "A" and coil tower. See Fig 2 .
Check insulation resistance of case. Using a 500-volt meter, measure insulation resistance between positive terminal and coil case. If resistance is not more than 10 megohms, replace ignition coil.

Fig 1: Checking Primary Coil Winding Resistance (Leading Side)

Courtesy of MAZDA MOTOR CORP.

Fig 2: Checking Primary Coil Winding Resistance (Trailing Side)

Courtesy of MAZDA MOTOR CORP.

IGNITION COIL RESISTANCE - Ohms @ 68°F (20°C)

Application	Primary	Secondary
Leading	0-1.0	9600-16,000
Trailing	0-1.0	Infinity