TEST OR INSPECTION
1. ONE OR MORE LAMPS FAIL TO LIGHT.
Remove and replace as required:
Check for continuity between edge of lamp socket and light assembly
housing and center post of lamp socket and related light assembly
If no continuity exists, replace light assembly:
Check continuity between edge of lamp socket and trailer frame.
If no continuity exists, clean mating surfaces.
Disconnect main harness from intervehicular cable. Have assistant
operate lights while you check voltage in affected lines of inter-
If 24 volts are present in all affected lines, replace main harness
Disconnect intervehicular cable from towing vehicle receptacle. Have
assistant operate lights while you check voltage at receptacle.
If 24 volts are present at receptacle, replace cable.
If 24 volts are not present at receptacle, check TM for towing
2. LAMPS DIM OR FLICKERING.
Check continuity between intervehicular cable pin D and ground wire
If no continuity exists, replace cable.