Primary Ignition Tests

1. Place ignition switch in the On position and connect a voltmeter between ignition coil positive terminal and ground.
a. If voltage is 5.5 to 6.5 volts, proceed to step 2.
b. If battery voltage is noted, proceed to step 4.
c. If voltage reading is below 5.5 volts, disconnect condenser lead. If voltage reading with capacitor lead disconnected is now 5.5 to 6.5 volts, replace capacitor. If reading is still not within limits, proceed to step 7.
2. Check voltage at ignition coil positive terminal while cranking engine.
a. If battery voltage is present, the ignition coil primary circuit is satisfactory.
b. If less than battery voltage is present, proceed to step 3.
3. Check short or open circuit at starter motor solenoid "I" terminal or for defective starter motor solenoid and repair or replace as necessary.
4. With ignition switch in the On position, disconnect electrical lead from starter motor solenoid "I" terminal and measure voltage at ignition coil positive terminal.
a. If voltage is now 5.5 to 6.5 volt, replace starter motor solenoid.
b. If battery voltage is indicated, proceed to step 5.
5. With ignition switch On and electrical lead disconnected at starter motor solenoid "I" terminal disconnected, connect a jumper wire from ignition coil negative terminal to ground and measure voltage at ignition coil positive terminal.
a. If battery voltage is still indicated, proceed to step 7.
b. If voltage reading is now 5.5 to 6.5 volts, proceed to step 6.

Fig. 1 American Motors (Motorcraft) Solid State Ignition (SSI) System. 1983 6-258 & 1984-85 4-150 Engines:

Fig. 2 American Motors (Motorcraft) Solid State Ignition (SSI) System. 1984-87 6-258 engines:

Fig. 3 American Motors (Motorcraft) Solid State Ignition (SSI) System. V8-360 engines:

6. Check continuity between ignition coil negative terminal and electronic control unit D4, Figs. 1 through 3. Also check continuity between electronic control unit terminal D1 and ground.
a. If continuity exist, replace electronic control unit.
b. If continuity does not exist, locate and repair open circuit, then repeat step 2.
7. Place ignition switch in the Off position and measure resistance between ignition coil positive terminal and dash panel connector terminal 13 or FW depending on model, Figs. 1 through 3.
a. If resistance is more than 1.4 ohms, replace resistance wire.
b. If resistance is between 1.3 and 1.4 ohms, proceed to step 8.
8. With ignition switch in the Off position, measure resistance between dash panel connector terminal 13 or FW ,depending on model, and ignition switch terminal I1, Figs. 1 through 3.
a. If resistance is less than .1 ohm, check for defective ignition switch or wiring from ignition switch to battery.
b. If resistance is more than .1 ohm, check for faulty connection at dash connector or ignition switch or defective wiring. After repairing, proceed to ignition coil test.