Game Composites GB1 GameBird, Maintenance Manual

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Maintenance Manual GB1 GameBird
Page date: April 24, 2020
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Voltage Regulator
When battery is not charged during normal operation or in case of abnormally high or low charging current:
1. Turn on master switch BAT and ALT , and circuit breaker Field . Measure voltage on battery bus and on
pin 6 of the regulator. The voltages should be equal within 0.5V. A difference of greater than 0.5V
may be caused by poor contacts in the circuit breaker, or poor crimp joints/loose terminals in the
wiring between the bus and pin 6. No voltage on pin 6 will prevent the regulator from operating.
2. Measure voltage on pin 4 of the regulator. The voltage should be approximately 1.2 volt less than that
on pin 6. A difference significantly less than 1.2V between pins 4 and 6 may indicate an open field
circuit from pin 4 through the alternator ground (-). Voltage differences of several volts could indicate
a faulty regulator. Ideal pin 4 voltage is 10.9 to 11.4 on a 12.6-volt bus.
3. Without disconnecting the field connector, measure the field voltage on the alternator. Use a thin
probe or small gage wire wrapped around the probe to reach through the connector body and
measure the voltage on the male blade coming out of the alternator. It should measure within 0.5V of
the measurement on pin 4 of the regulator. A lack of voltage may indicate an open circuit between
pin 4 of the regulator and the field terminal. If an open field circuit is suspected, turn system OFF,
disconnect alternator field connector, and measurement resistance between the connector and pin 4
of the regulator. Look for near 0 Ohms. Typically, the field resistance of the alternator will be between
3 and 10 Ohms from the male field terminal blade to alternator case.
4. With switches ON, check the voltage between the alternator output post (or B-lead) and ground. It
should be battery voltage. If not, check the wiring between the alternator B-lead and the battery
positive (+) terminal. Look for loose or contaminated connections, broken wires or an open breaker or
fuse.
5. If all of the voltages in the steps above are close to the value specified, the charging system should be
operative. If not, check for broken or loose alternator drive.
Master Relay
When no power supply to any part of the electrical system:
1. Turn all switches OFF. Turn on BAT switch and listen for a clicking sound from the master relay.
2. If relay does not click, measure battery voltage to verify battery condition.
3. If battery is operational, measure voltage on the terminal of the relay connected to battery positive
(+). The measurement should be equal to the battery voltage. If not, there may be a problem with the
cable, crimps or terminal connection.
4. When battery provides sufficient power and connection from battery to the relay is OK, the relay may
be damaged.
5. If the relay engages when BAT switched on, measure the voltage on the output terminal of the relay.
The measurement should equal to the battery voltage. If not, the relay is damaged.
Starter Relay
Insufficient power to crank the engine:
1. Disconnect the relay from the circuit. Measure the resistance between the two bigger terminals with
appropriate ohmmeter scale. The ohmmeter should show high reading. If the reading is low, replace
the relay.
2. Attach a positive battery jumper to one of the two smaller terminals and a negative battery jumper to
the other. The relay should engage (make a click sound). If not, replace the relay.
3. Measure the resistance between the two smaller terminals with the relay engaging. The ohmmeter
should show a low reading. If not, replace the relay.
4. After installation, measure the resistance between the ground and the relay case. A very low or 0
reading is expected. If the measurement is high, check the connection of the grounding wire from the
relay foot to GND1.