Bendix Commercial Vehicle Systems TROUBLE SHOOTING COMPRESSOR User Manual
Page 12
Symptom:
What it may indicate:
What you should do:
12
15.0 Compressor
constantly cycles
(compressor
remains unloaded
for a very short
time.)
(a) Air brake charging system
maintenance not performed.
(b) Compressor unloader mechanism
malfunction.
(c) Air dryer purge valve or delivery
check valve malfunction.
(d) Air brake system leakage.
Available reservoir capacity may be
reduced by build up of water etc. Drain and
perform routine maintenance per Table A,
columns 3 & 4, on page 3.
Go to Test 6 on page 15.
Verify operation of air dryer. Follow vehicle
OE maintenance recommendations and
component Service Data information.
Go to Test 2 on page 14.
14.0 Air dryer
doesn’t purge.
(Never hear
exhaust from air
dryer.)
(a) Air dryer malfunction.
(b) Governor malfunction.
(c) Air brake system leakage.
(d) Improper governor control line
installation to the reservoir.
Verify operation of air dryer. Follow vehicle
OE maintenance recommendations.
Go to Test 4 on page 15.
Go to Test 2 on page 14.
Go to Test 5 on page 15.
12.0 Air dryer
safety valve
releases air.
(a) Restriction between air dryer and
reservoir.
(b) Air dryer safety valve malfunction.
(c) Air dryer maintenance not
performed.
(d) Air dryer malfunction.
(e) Improper governor control line
installation to the reservoir.
(f) Governor malfunction.
Inspect delivery lines to reservoir for
restrictions and repair as needed.
Verify relief pressure is at vehicle or
component manufacturer specifications.
Replace if defective.
See Maintenance Schedule and Usage
Guidelines (Table A Column 3, on page 3).
Verify operation of air dryer. Follow vehicle
O.E. maintenance recommendations and
component Service Data information.
Go to Test 5 on page 15.
Go to Test 4 on page 15.
13.0 Reservoir
safety valve
releases air
(a) Reservoir safety valve malfunction.
(b) Governor malfunction.
(c) Compressor unloader mechanism
malfunction.
Verify relief pressure is at vehicle or
component manufacturer's specifications
(typically 150 psi). Replace if defective.
Go to Test 4 on page 15.
Go to Test 6 on page 15.
Technician removes
governor.
Air dryer
safety valve