Piper Dakota Maintenance Manual page 377

CHART 370L. TROUBLESHOOTING (VACUUM SYSTEM) (CONT,D)
AIRCRAFT WITH AUXILIARY VACUUM PUMP SYSTEMS
TROUBLE
AUX ON selected on
ground check and
auxiliary vacuum pump
will not run
AUX ON selected on
ground check and little
or no vacuum is in-
dicated.
AUX ON annunciator
will not light.
VAC OFF AUX ON
annunciator switch
will not engage auxiliary vacuum
pump system.
Auxiliary vacuum pump
maintains correct
pressure on ground
but not at altitude.
PIPER AIRCRAFT
PA-28-236
MAINTENANCE MANUAL
CAUSE
Circuit breaker open.
Faulty electrical motor.
Faulty contactor.
Loose or broken wire
connections.
Leak in vacuum system.
Restriction in hose
lines.
Dirty filter.
Faulty bulb.
Regulator not adjusted
properly.
Open circuit breaker.
Faulty switch.
Auxiliary vacuum pump
is worn.
Regulator is sticky.
2E5
REMEDY
Push circuit breaker(s)
in.
Isolate and check op-
eration. Replace pump/
motor assembly if re-
quired.
Check operation. Replace
if required.
Tighten all wire con-
nections and terrninals.
Check all wires for open
breaks and repair ac-
cordingly.
Tighten clamps and check
hoses. Replace if nec
essary.
Inspect and repair hose
lines. Replace if nec-
essary.
Replace filter.
Replace bulb.
Adjust properly.
Push circuit breaker(s)
in.
Test switch for operation.
Replace if necessary.
Replace auxiliary vacuum
pump assembly.
Clean or replace regu-
lator.
37 - 02 - 00
Page 37 - 03
Reissued: August 1, 1986