TM 5-4240-5501-148P
STARTERS
Starter Generator 12V
CHECKING
STARTER-GENERATOR
AND
REGULATOR (See Fig. 132)
NOTE: All tests to be made with ignition off and starter
switch pressed long enough for meter needle to settle.
1.
Checking Ground Resistance (Poor Connection)
Plug black lead in black common meter socket and
red lead
in
VOLTS-OHMS
LEAKAGE
socket.
Negative test lead to #1 (ground). Positive test lead
to #2. Press starter switch. Meter should read 10
volts or more.
2.
Checking Lead to Switch Leave negative test lead at
ground #1. Move positive lead to #3. Low or no
voltage
reading
while
pressing
starter
switch
indicates
defective
positive
battery
cable
or
connection.
3.
Checking Starter Switch Move the positive test lead
to #4. The meter should read "close to battery
voltage" when starter switch is pressed. Very low or
no voltage indicates a defective starter switch.
4.
Checking Lead from Switch to Starter Move the
positive test lead to #5. Press the starter switch.
The meter should read "close to battery voltage." If
the starter motor does not crank and battery voltage
is available, the starter motor is defective. If voltage
is not available, cable or connection between
testpoint #5 and #4 is defective.
5.
Generator-Regulator Test Set test meter at 15 amps,
put red lead in AMP socket. Disconnect wire at
voltage regulator terminal "B," and connect test
instrument in series. The meter will register charge,
if any, to the battery when the engine is running. The
charge will start approximately 1800 to 2000 engine
RPM, and will vary according to the battery state of
charge.
If meter reads 10 amps or more, disconnect "F"
terminal at regulator. If output remains high, the
generator is defective. If output stops, the regulator
is defective.
If no charge is shown on meter, short the regulator
"F" terminal to ground. Meter should then show a 10
amp or more charge. No charge would indicate a
defective generator. A charge would indicate a
defective regulator.
Fig. 133 - Voltage Regulator
42
