Suzuki WagonR+ RB310 Service Manual page 2673

6H-4 CHARGING SYSTEM
DIAGNOSIS
COMMON CAUSES OF FAILURE
A battery is not designed to last indefinitely; however, with proper
care, it will provide many years of service. If the battery performs
satisfactorily during test but fails to operate properly for no apparent
reason, the following are some factors that may point to the cause
of trouble:
D Accessories left on overnight or for an extended period without
the generator operating.
D Slow average driving speeds for short periods.
D Electrical load exceeding generator output particularly with addi-
tion of aftermarket equipment.
D Defects in charging system such as high resistance, slipping
drive belt, loose generator output terminal, faulty generator or
voltage regulator. Refer to "GENERATOR" in this "DIAGNOSIS"
section.
D Battery abuse, including failure to keep battery cable terminals
clean and tight or loose battery hold down.
D Mechanical problems in electrical system such as shorted or
pinched wires.
VISUAL INSPECTION
Check for obvious damage, such as cracked or broken case or cov-
er, that could permit loss of electrolyte. If obvious damage is noted,
replace battery. Determine cause of damage and correct as need-
ed.
HYDROMETER TEST
The direct method of checking the battery for state of charge is to
carry out a high rate discharge test, which involves a special pre-
cise voltmeter and an expensive instrument used in the service
shops, but not recommendable to the user of the vehicle.
At 20_C of battery temperature (electrolyte temperature):
– The battery is in FULLY CHARGED STATE if the electrolyte spe-
cific gravity is 1.280.
– The battery is in HALF CHARGED STATE if the specific gravity
is 1.220.
– The battery is in NEARLY DISCHARGED STATE if the specific
gravity is 1.150 and is in danger of freezing.
As the specific gravity varies with the temperature, if battery tem-
perature is not at 20_C (68_F), you have to correct your specific
gravity reading (taken with your hydrometer) to the value at 20_C
(68_F) and apply the corrected specific gravity value to the three-
point guide stated value.
For the manner of correction, refer to the graph showing the relation
between specific gravity value and temperature at the left.