Noise from a generator may be caused by one of the following
conditions:
A high frequency whine or magnetic noise may be heard at full output.
This is a normal condition.
Perform an output test in order to help distinguish bearing noise from
the magnetic noise, also called a whine. Refer to
Generator Not Operating Properly
. A
shorted bridge diode will reduce output and have a growling noise at high
load. It is also helpful to listen to the generator with a moderate load
(engine cooling fans or headlights ON) in order to determine if there
is a bearing or magnetic noise.
In order to avoid damage to the electrical equipment, observe the following
precautions:
| • | Do not reverse the connections to the generator. |
| • | Do not short across or ground any of the terminals in the charging
circuit except as directed by the service manual. |
| • | Do not apply the battery voltage directly to the regulator L terminal
for testing. A 400 - 500 ohm resistor must be used. |
| • | Never disconnect the battery cables from the output terminal or
the battery while the generator is operating. |
| • | When connecting a charger or booster battery to the car battery,
refer to
Battery Charging
. |
Trouble in the charging system can be indicated by the following conditions:
| • | The battery indicator does not light with the ignition switch
in the ON position before the engine start, or does not go out after the engine
start. |
| • | Service Engine Soon light comes ON. |
| • | An overcharged battery as evidenced by spewing of electrolyte
from the vents. |
If an undercharged or overcharged battery condition occurs, the following
procedure may be used to diagnose the charging system:
- Visually inspect the accessory drive belt for damage or looseness.
- Inspect the charging circuit electrical connections for damage
or looseness.
- Perform the Generator Electrical Test. Refer to
Generator Not Operating Properly
.
