TM 9-2330-297-14&P
NOTE
Semitrailer must be hooked up to the towing vehicle when performing electrical or
airbrake system tests.
ORGANIZATIONAL TROUBLESHOOTING
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
ELECTRICAL SYSTEM
1. ALL LAMPS FAIL TO LIGHT.
Step 1. Check towing vehicle circuit breakers and fuses.
Reset circuit breaker and replace bad fuses. See towing vehicle technical manual.
Step 2. Check for open circuit in intervehicular cable.
Military towing vehicles
Have an assistant apply brakes on towing vehicle.
Using multimeter, check voltage between contact D and contacts B, E, and J of intervehicular
cable plug (1). Multimeter should read 24 volts.
Commercial towing vehicle
Have an assistant apply brakes on towing vehicle.
Using multimeter, check voltage between contact 1 and contacts 2, 3, 4, 5, and 6 of intervehicular
cable plug (2). Multimeter should read 12 volts.
If improper or no reading is obtained, troubleshoot towing vehicle as described in towing vehicle
technical manual.
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