The 1989 Jeep Wrangler TJ Starting System consists of battery, starter relay, starter within an integral solenoid, ignition switch, clutch pedal position switch for manual transmission system, park/neutral position switch for automatic transmission, and wire harness/connectors.
The starting system components form two separate circuits. A high-amperage feed circuit that feeds the starter between 150 and 350 amperes, and a low-amperage control circuit that operates on less then 20 amperes. If the vehicle is equipped with an automatic transmission, battery voltage is supplied through the low amperage control circuit to the coil battery terminal of the starter relay when the ignition switch is turned to the Start Position.
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