Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Alternator & Regulator: Description
Bosch conventional 3-phase, self-rectifying type alternators use 3 exciter diodes connected to stator windings. These diodes turn off alternator indicator light and supply power to voltage regulator while engine is running. Bosch regulators are transistorized and integral with alternator.
An unloader relay is used in the 735 series. With ignition On and engine off, the relay receives battery voltage (B+) through fuse No. 28 and is grounded through terminal D+ of the alternator. The relay energizes and switches ground to some accessories. When the engine is running and alternator begins to charge, battery positive voltage is also applied to terminal D+ to switch off the relay.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.