TM 55-1930-209-14&P-12
f.
Open (OFF) 24 Vdc circuit breaker 6P14 and disconnect wires from TB2 and TB3 at timer terminal board. Check
continuity of remote circuit between two wires from TB2 and TB3. With remote switch closed, circuit must be
closed and with remote switch opened, circuit must be open. If improper operation exists, go to step (1). If
proper operation exists, go to step g.
(1)
Check continuity between points S1 and S2 at switch SW when switch is closed and open circuit when
switch is open. If switch indicates proper operation, go to step (2). If switch indicates improper operation,
replace switch.
(2)
Check continuity between point S1 at switch SW and TB4 and between point S2 at switch SW and TB5 at
remote control assembly. If open circuit exists, repair or replace cable from remote control terminal board
to remote switch SW. If continuity exists, repair or replace cable from remote control assembly TB4 and
TB5 to timer TB2 and TB3 Reconnect all wires.
g.
Reconnect all wires from step f and disconnect wires from TB4 and TB5 at oscillator/regulator PC assembly.
With remote PB-SW switch pressed, check continuity of circuit between wires from TB4 and TB5. If continuity
does not exist go to step (1) if continuity exists, go to step h.
(1)
With remote switch PB-SW pressed, check continuity between points R1 and R2 at switch. If continuity
exists, go to step (2). If continuity does not exist, replace switch remote PB-SW as given in paragraph 3-
17.4.
(2)
Check continuity of wires from switch PB-SW to remote assembly terminal board between points R1 and
TB2 and points R2 and TB3. If both checks indicate closed circuit, go to step (3). If either check indicates
an open circuit, repair or replace faulty wire(s).
(3)
Check resistance of resistor between points T1 and T2 for 1000 ohms. If resistance is 1000 ohms, go to
step (4). If resistance is not 1000 ohms, replace resistor.
(4)
Check continuity of wire from 1000 ohm resistor to remote assembly terminal board between points T1 and
TB2 and points T2 and TB1. If continuity exists, replace cable from oscillator/regulator PC assembly TB4
and TB5 to remote control assembly-TB1 and TB3. If continuity does not exist, replace wire(s) from
remote control assembly TB1 and TB3 to 1000 ohm resistor point T1 and T2. Reconnect all wires.
h.
Close (ON) 24 Vdc circuit breaker 6P14 and check for negative voltage at oscillator/regulator between terminals
2 (+) and 5 (-) for 12 Vdc. This voltage should correspond to the timer characteristic which is 2 seconds ON and
18 seconds OFF. If voltage is 12 Vdc, go to step 1. If voltage is not 12 Vdc or does not correspond to the timer
characteristic, replace timer.
i.
Check voltage at oscillator/regulator between terminals 6 and 7 for approximately 24 Vac. This voltage should
correspond to the timer characteristic which is 2 seconds ON and 18 seconds OFF. If voltage is not
approximately 24 Vac or is out of time, go to step j. If voltage is approximately 24 Vac and is in time, go to step
(k).
j.
Check the fuse in the oscillator/regulator. If the fuse is blown, replace it with a AGC-5 buss or equivalent (API
Part No 4035 0022). If the new fuse does not blow, go to step k. If the new fuse blows, replace the
oscillator/regulator.
k.
Check voltage at driver unit between points 1 and 2 for 24 Vac. This voltage should correspond to the timer
characteristic which is 2 seconds ON and 18 seconds OFF. If the voltage is not approximately 24 Vac, replace
input wire(s) to drive unit. If voltage is approximately 24 Vac, replace the driver unit.
3-6
