Solid State Ignition System: Notes

The Grand Wagoneer 5.9L engine is equipped with a Solid State Ignition (SSI) system. The SSI system consists of ignition module, ignition coil, resistance wire, and distributor (pick-up coil and trigger wheel). Base ignition timing is adjustable with this system.

The ignition module is activated when ignition switch is in the START or ON position. The primary circuit is closed and current flows through the coil primary winding. When camshaft turns distributor, the trigger wheel teeth rotate past the pick-up coil assembly (in the distributor). As each tooth aligns with the pick-up coil, the resulting pulse triggers the ignition module which opens the coil primary circuit. A high voltage is then induced in the coil secondary winding and current flows to the distributor cap and rotor. As the rotor spins it distributes high voltage to the proper spark plug. Ignition timing is constantly changed by electronic, vacuum, and centrifugal advance mechanisms according to engine operating conditions.