TM 5-4220-233-14
4-12. TROUBLESHOOTING PROCEDURES
Table 4-2. Unit Troubleshooting.
MALFUNCTION/SYMPTOM
PROBABLE CAUSE
TEST OR INSPECTION/CORRECTIVE ACTION
ELECTRICAL SYSTEM
1.
ONE OR MORE (NOT ALL) LAMPS FAIL TO LIGHT
WARNING
When troubleshooting an electrical malfunction, ALWAYS disconnect
intervehicular electrical cable from towing vehicle. Failure to do so may
result in injury or death due to electrical shock.
NOTE
Refer to Figure 4-42, paragraph 4-51 to determine routing of electrical wires and
location of electrical components
Individual lamp burnt out.
Check and replace lamp.
Individual lamp sockets damaged.
Perform continuity check and replace light as required.
Bad connection between wire harness and light.
Check connection between wire, wire harness and light, tighten or repair as required.
Damaged wire in wire harness or bad connection at junction block.
Perform continuity check between junction block and connection at light.
Damaged wire between fusible link and junction block.
Check for loose connection or damaged wire and repair as required.
Fusible link failed open.
Perform continuity check on fusible link. Replace if defective.
Damaged wire/pin on Intervehicular cable or bad connection to fusible link.
Perform continuity check between intervehicular cable and fusible link.
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