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Alternator bad diode - Suzuki Cars & Trucks

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is this a question,?
1: is mine bad, how to test it or find it, in the global sense?
2: where to buy one.
3: which brands are best.
4: how to do a basic diode test , front to back ratio testing.
5: what are the symptoms of a bad diode.

ill throw the ice 2+3 = 5.
the Modern ALT has many diodes. (and more{in dah reg})
the 2 main, sets are , the 3 phase set.
and the keep alive pack.
ill not cover the keep alive pack or the regulator diodes..
the 3 phase pack take the 3 AC phases and converts them to Pulsating DC. (in effect simulating a DC generator)
if 1 diode opens , you lose, 1/3 of the total power.
so 50 amp alt is now a 33 amp alt. (weak as a cat)

if the diode shorts, it becomes this huge noise generator.
(turn on the AM radio , here it sing and raise pitch as you gun the throttle (i use a scope to see bad diodes) bingo.
the noise can in fact cause any electronics on the car to go nuts.

the diodes also have one other feature, ill skip here, (zener actions)

Posted on Nov 19, 2013


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