Pickup test: Disconect the neg. bat. cable. Connect your ohm meter to the two leads to the pickup. Resistance must be within 400-1000 ohms. If not, replace the pickup.....been there.

Coil test-Primary: Disconnect the neg. bat. cable or disconnect the neg. wire on the coil. Read with your ohmmeter between the positive and negative terminals on the coil. Resistance should be less than 1-2 ohms.

Coil Test-Secondary: Measure with your ohm meter between the neg.terminal on the coil and the secondary output terminal/tower on the coil. Should be between 700 and 12,000 ohms. If you read infinity or very low resistance, the coil is bad.
Hope I could help.