TROUBLE SHOOTING
EN / Alpha alternator - Alpha Pro II regulator / January 2013
25
8 TROUBLE SHOOTING
In case of any issue, we recommend consulting the Maintenance section first (see section 1). If you cannot solve
a problem with the aid of the table below, contact your local Mastervolt Service Centre. See www.mastervolt.com.
ISSUE
POSSIBLE CAUSE
SOLUTION
The three LED’s of the Alpha
Pro II are blinking together.
•
This is the start up mode of the
Alpha Pro II. After this the Alpha
Pro II starts regulating.
This is a normal situation. Wait until the
LED’s stop blinking.
The three LED’s of the Alpha
Pro II are blinking
alternately.
•
The Alpha Pro II selector is on a
blank spot. The MasterBus alarm
Invalid System
is shown.
Check the selector and correct its
position.
The three LED’s of the Alpha
Pro II are blinking twice
alternately.
•
The Alpha Pro II MasterBus
configuration was unlocked, it has
stopped regulating.
Adjust the settings and relock the
configuration. The Alpha Pro II enters the
start up mode after this.
Your oil pressure light (if
installed) is blinking twice
each time.
•
The selector is in the 12V position,
while your alternator and battery
are 24V. The Alpha Pro II is not
regulating.
Check the selector and correct its
position.
No voltages at all. All LED’s
of the Alpha Pro II regulator
are off.
•
Battery fuse has blown.
Investigate the cause of this malfunction.
Then replace the fuse.
•
Battery connections are corroded
or bad.
Clean and tighten the connections. If the
cables are burned, replace them.
•
Black [gnd] wire is loose.
Check black [gnd] wire.
No output power, all LED’s
of the Alpha Pro II regulator
are off. Voltage on the [+bat]
terminal is 12/24V Voltage
on the [reg-on] terminal of
the regulator is 0V.
•
Engine is not running.
Start the engine.
•
2 Amps fuse in brown wire is
blown.
Check the 2 Amps fuse and replace if
necessary.
•
Problem with the oil pressure
switch or ignition relay (S1) or
brown [reg on] wire is loose.
Check voltage on [reg on] terminal of the
Alpha Pro II regulator. Check brown [reg
on] wire. Check the oil pressure contact or
ignition relay for correct operation.
No output power, one of the
LED’s of the Alpha Pro II
regulator is on. Voltage on
the [field] terminal of the
regulator is 0V.
•
10 Amps fuse in the red wire
blown.
Check the 10 Amps fuse and replace if
necessary.
•
Two pole field connector of the
cable assembly is loose (red and
blue wire).
Check field connector on the alternator
(reference 3 on the installation drawings).
•
Problem in the wiring.
Check red and blue wires to the field
connector.
•
Blue [field] wire is loose.
Check blue wire (reference 6 on the
installation drawings).
•
Field windings of the alternator are
defective.
Check resistance of field windings.
Replace alternator.
No output power, All LED’s
of the Alpha Pro II regulator
are off. Voltage on the [reg
on] and the [+bat] terminal of
the regulator are both
12/24V.
•
Black [gnd] wire is loose.
Check black [gnd] wire (reference 2 on
the installation drawings).
•
Alpha Pro II regulator defective.
Replace Alpha Pro II regulator.
Tachometer indication is too
low or fluctuates.
•
An alternator driven tachometer
may reduce its reading or fluctuate
when the Alpha Pro II regulator
makes a transition from absorption
to float if the battery is fully charged
with no loads or if the float voltage
is set quite low.
Nothing, this is a normal situation. To
avoid this, you may switch on some loads.
•
Engine speed is too low.
Increase engine speed.
•
Wrong calibration of the
tachometer.
Adjust tachometer according to pulley
ratio.
