Troubleshooting At The Alternator - Hatz 2-4L30 Workshop Manual

Trouble-shooting table for electrical system
Trouble-shooting at the alternator
Malfunction
Generator telltale
light does not go out
as engine speed
increases.
Generator telltale light
does not go out at low
engine operating speed
(e.g. 1500 rpm)
Generator telltale light
glows only dimly when
engine is stopped and
pre-heat/start switch is
operated, battery not
being charged, or char-
ging only at a low rate.
Cause
Line D+/61 has a short to earth.
Voltage regulator on generator
is defective.
Wiring connections interchan-
ged at generator.
V-belt for generator is slipping
or broken.
Defective rectifier on generator,
dirty sliprings, short-circuit in
line DF or rotor winding.
Generator is not sufficiently
excited by telltale light. A 2 Watt
bulb is normally used in the
light.
Rate of charge too low, brief
engine operating periods (parti-
cularly when a maintenance-
free, vibration-proof battery is
used).
Poor connections, open circuit,
contact resistance or short-cir-
cuit in charging circuit.
Battery is defective, internal
short-circuit.
Battery capacity has dropped
severely through being left flat
for a long time (sulphate depo-
sits).
Battery capacity is too large.
Alternator is defective.
Voltage regulator is defective.
Loose V-belt at alternator
Remedy
Renew the line or repair the short to
earth.
Renew voltage regulator.
Connect the wiring correctly.
Correct V-belt tension or renew V-
belt.
Repair generator
Install a bulb of higher rating, e.g. 2
W -> 3 W.Warning: bulb ratin must
not exceed 5 W (or pre-exciter circuit
will be destroyed)
Short-term remedy: recharge battery
with a suitable charger.Long-term
remedy: use a battery with better
charge characteristic.
Repair the break, clean the battery
terminals, tighten loose clamps.
Renew battery.
Recharge battery at low current for
about 50 hours. (Only possible if
sulphate deposits are not too exten-
sive); otherwise: renew battery.
Install a smaller battery or a larger
alternator.
Repair alternator.
Renew voltage regulator.
Correct V-belt tension.
L / M . . / 07.96
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