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Remove the Phillips screws that retain the cover, and then remove the cover. Remove the two
screws that hold the controller to the enclosure. Stuck relay contacts may open if jarred, so
gently move the controller to access the points as shown in Figures 7F and 7G. With a multi-
meter set to measure resistance, measure across the relay contacts as shown in Figure 7F. If
there is continuity, the contacts have welded closed and the relay board assembly will need to
be replaced. If the meter shows an open circuit, measure the resistance of the relay coil as
shown in Figure 7G. Normal resistance reading will be between 2,000 and 3,500 ohms. If the
measured resistance displays an open, low reading, or short circuit, the relay coil has failed
and the controller will need to be replaced.
Figure 7F
Figure 7G
If the relay contacts and relay coil both test OK, a test to verify if the electronic charge
controller has malfunctioned can be made if a precision digital type DC voltmeter is available.
Connect the charger to the battery pack and allow it to charge normally. After the charge
output amperage has tapered to its lowest point, measure the battery terminal voltage using a
DC voltmeter capable of reading in increments of .001 volts. Continue charging and check the
battery voltage reading every hour. If the battery voltage increases less than .072 volts, or if
the battery voltage decreases between successive hourly readings, the charger should turn off.
If the charger does not turn off, the electronic charge controller has malfunctioned and must be
replaced.
8. TRANSFORMER
TESTING
Failure of the transformer can be the result of natural aging, premature shorting of adjacent coil
turns or overheating damage. The most common cause of transformer overheating and
premature burnout is the result of misuse, connecting the charger to a battery system of lower
voltage than specified on the charger. Darkening of all the transformer secondary coil
windings is an indication of possible overheating damage. A low or complete lack of output
would be observed on the ammeter; however, the transformer may hum or the AC line fuse or
circuit breaker may blow when the charger is turned on.
The purpose of this test is to confirm the AC output voltage of the transformer. Please read,
review, and understand this entire testing procedure before you perform this test.
