Demco CR 108, Operator'S Manual

Page: 44 / 104

44
Malfunction Probable Cause Corrective Action
All lights fail to A. Inter-vehicular cable not properly plugged A. Pull plugs out and reinsert them.
light. into receptacles on semi-trailer and towing be sure plugs seat properly.
vehicle.
B. Light switch on towing vehicle B. Check light switch.
malfunctioning.
C. No current from towing vehicle. C. Check circuit breaker and wiring
on towing vehicle.
D. Short circuit in wiring. D. Check wiring for bare spots in insulation.
E. Dirty or corroded contacts in receptacle E. Clean receptacle and plug.
or on plug of inter-vehicular cable.
F. Dirty or corroded contacts in connectors F. Clean corroded contacts in connectors.
of semi-trailer wiring.
Lights burn dim A. Loose, dirty, or corroded terminals. A. Clean and tighten terminals.
or flicker.
B. Poor or loose ground. B. Clean and tighten terminals on short
(ground) cable in back if receptacle
assembly on semi-trailer
C. Defective lamps. C. Replace defective lamps.
D. Dirty or corroded lamp socket or contact in D. Clean or replace lamp socket,
receptacle or on plug of inter-vehicular cable. receptacle or plug.
Individual lamps A. Burned out lamp. A. Replace lamp.
do not light.
B. Broken or loose connection. B. Check cables for brakes and poor
connections. Tighten, repair or replace.
Clean connections.
C. Damaged light assembly. C. Repair or replace light assembly.
D. Dirty or corroded lamp socket. D. Remove lamp and clean contacts.
E. Dirty or corroded contact in receptacle or E. Clean receptacle and plug.
on plug of inter-vehicular cable.
Troubleshooting
Electrical System