Table 4-4. Voltmeter-Ammeter Range Selector Switch Continuity Check
Check for Continuity Between Terminals
* Terminal 17 is jumped to terminal 18.
continuity. With the switch in the ON position, there
should be continuity. Replace switch if necessary.
(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 con-
tinuity is not found for each set of terminals listed,
(11) Relays (K1), (K2), (K3), Assembly A-1, CR-1, and
CR-2. Open circuit breaker (CB2). On ASK equipped generators,
remove batteries access door. Disconnect battery cable. Tag, dis-
connect and tape terminals lugs of the following: A1 and A2 on
crank relay (K3), A1 and A2 on 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 A1Test for shorted or
open diodes CR-1 and CR-2 by using an ohmmeter. Connect posi-
tive lead of the ohmmeter to A1-5 and negative lead to A1-6,
ohmmeter should indicate high resistance, then reverse the leads
and ohmmeter should indicate low resistance. Connect positive
lead of the ohmmeter to A1-7 and negative lead to A1-8, ohm-
meter should read high resistance, then reverse leads and ohm-
meter should read low resistance. Replace defective diodes that
fail the above test. Reconnect wire to A1-5, A1-6, A1-7, and
A1-8 to A1 relay assembly. 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 A1-3 and A1-4 on A1 relay assembly. Con-
tinuity should end when master switch is released. Repeat test for
preheat relay K2 holding master switch in PREHEAT position. Re-
place defective relays. Reconnect wires to relay K2, K3, and A1
(12) Terminal Board Assemblies (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 indi-
cated 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 ohmmeter check primary winding by measuring
resistance from terminal H1 to H2. Resistance
should be 18.6 ohms ± 1.86 ohms. Check secondary
winding bv 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 re-
sistance, replace transformer.
(15) Transformer (T2) (see figure 4-33). Tag
and disconnect four leads to transformer T2. Check
primary winding by measuring resistance from ter-
minal H1 to H2. Resistance should be 155 ohms
± 15.5 ohms. Check secondary winding by measuring
resistance from terminal X1 to X2. Resistance should
be 18.8 ohms ± 1.88 ohms. If either of the windings
do not show the proper resistance, replace trans-
(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 Transducer (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 control cubicle.