TM 9-2330-359-14&P
Table 4-2. Organizational Troubleshooting.
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
ELECTRICAL SYSTEM
1. ALL LAMPS FAIL TO LIGHT.
WARNING
When troubleshooting an electrical malfunction, ALWAYS disconnect towing vehicle
electrical connector from semitrailer. Failure to do so may result in serious injury or
death due to electric shock.
N O TE
Refer to wiring diagrams in paragraph 4-29 to determine routing of electrical wires and
location of electrical components.
Step 1.
Step 2.
Step 3.
Step 4.
Check for unserviceable circuit breaker on towing vehicle.
Replace defective circuit breaker. Refer to towing vehicle technical manual for instructions.
Check for open circuit in wiring.
Replace or repair wiring harness as required (para 4-27 or 4-28).
Check for loose connections and good ground wire contact inside nose box.
Clean and tighten connections.
Check all electrical receptacles, connectors, and lamps for broken and defective components.
Replace broken and defective components (paras 4-19 through 4-26).
2. ONE OR MORE LAMPS (BUT NOT ALL) FAIL TO LIGHT.
WARNING
When troubleshooting an electrical malfunction, ALWAYS disconnect towing vehicle
electrical connector from semitrailer. Failure to do so may result in serious injury or
death due to electric shock.
NOTE
Refer to wiring diagrams in paragraph 4-29 to determine routing of electrical wires and
location of electrical components.
Step 1.
Check for broken wiring harness or loose connection.
Tighten, replace or repair wiring harness (para 4-27 or 4-28).
Step 2.
Check for dirty or corroded lamp socket.
Remove lamp and clean contacts and socket.
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