Table 4-4. Voltmeter-Ammeter Range Selector Switch Continuity Check
Check for Continuity Between Terminals
* Terminal 17 is jumped to terminal 18.
(10) Ammeter-Voltmeter Transfer Switch (S8).
Tag and disconnect sixteen leads to range selector switch.
Check for continuity between terminals for each of the
six switch positions as given in table 4-4. If continuity
is not found for each set of terminals listed, replace switch.
(11) Relays (K1), (K2), (K3), relay assembly (A1), diodes
(CR1) and (CR2) (see figures 1-7 and 4-33). Open circuit breaker
(CB2). On ASK equipped generators, remove batteries access
door. Disconnect battery cable. Tag, disconnect and tape the
following terminal lugs: A1 and A2 on crank relay (K3), preheat
relay (K2), and A1-4 and A1-3 on relay assembly A1. Tag and
disconnect terminals A1-5, A1-6, A1-7, and A1-8 on relay assembly
A1. Tact diodes CR1 and CR2 for shorted or open condition with
ohmmeter. Check CR1 by connecting positive lead of ohmmeter
to A1-5 and negative lead to A1-6. Ohmmeter should indicate
high resistance. Reverse ohmmeter leads. Ohmmeter should read
low resistance. If either CR1 or CR2 fails the above test, the
diode is defective and must be replaced. Reconnect terminals to
A1-5, A1-6, A1-7, and A1-8 on relay assembly A1. Reconnect
battery cable. Close circuit breaker (CB2). Hold master switch
in START position and using an ohmmeter check for continuity
between terminals A1 and A2 on crank relay K3, and continuity
between A1-3 and A1-4 on relay assembly A1. Continuity should
end when master switch is released, Repeat the above continuity
test for preheat relay K2 while holding master switch in
PREHEAT position. If either K2 or K3 fail the continuity test, the
relay is defective and must be replaced. Reconnect terminals A1
and A2 to relay K2 and K3, and terminals A1-4 and A1-3 to
relay assembly A1.
(12) Terminal Board Assembly (TB4) and (TB5). Tag and
disconnect leads to terminal boards. Test from each terminal to
ground for shorts. Replace board if any terminal shows continuity
On ASK equipped generators, access to J1 and J2
is through air intake door.
(13) Wiring Harness. Test wiring harness by using an
ohmmeter checking continuity of each wire. Perform point to
point checks between points indicated on figure 1-10. Wiring
harness need not be totally disconnected for checking continuity.
(14) Transformer (T1) (see figure 4-33). Tag and
disconnect five leads to transformer T1. Using an ohm-
meter check primary winding by measuring resistance
from terminal H1 to H2. Resistance should be 18.6
ohms ± 1.86 ohms. Check secondary winding by measuring
resistance from terminal X1 to X3. Resistance should
be 1.6 ohms ± .16 ohms. If either of the windings do not
show the proper resistance. replace transformer.
(15) Transformer (T2) (see figure 4-33). Tag and
disconnect four leads to transformer T2. Check primary
winding by measuring resistance from terminal H1 to H2.
Resistance should be 155 ohms ± 15.5 ohms. Check sec-
ondary winding by measuring resistance from terminal Xl
to X2. Resistance should be 18.8 ohms ± 1.88 ohms. If
either of the windings do not show the proper resistance,
(1) Control Cubicle. On ASK equipped generators, remove
rear panel assembly (para. 5-7). Open air intake door. Tag and
detach two connectors for wiring harness from control cubicle (see
figure 1-2). Remove screw (6, figure 4-34) and nut (8) attaching
ground strap to cubicle support frame. Remove four screws (2),
Iockwashers (3) and flatwashers (4) attaching control cubicle to
vibration mounts (5) and remove cubicle (1).
(1) Inspect the control cubicle assembly per
(2) Frequency Tranducer (A3) (see figure 4-33).
Inspect transducer for physical damage. Check to see that
the electrical connections to transducer are clean and tight.
Check to see that transducer is securely attached to the