Charging System

With the ignition switch in START or RUN, voltage is present at the charging system indicator through Gray/Blue wire. When the engine is not running, or when the engine is running and the generator/voltage regulator output is below a preset value, the generator/voltage regulator grounds the charging system indicator through Yellow/Blue wire and Yellow/Black wire and the diode junction box, causing the indicator to light. At the same time the Blue/Yellow wire is grounded by the generator/voltage regulator via the diode junction box. This grounds the bulb check relay coil. The relay is energized, applying ground to the Yellow/Purple and the Yellow/Purple wire, also causing the brake warning indicator to light.

If the engine is running and the charging system is working properly, the generator/voltage regulator removes ground from Yellow/Blue wire and the Yellow/Black wire and the diode junction box and charging system indicator and brake warning indicator turn off. See Figure .