TM 9-2330-381-14
4-13. TROUBLESHOOTING (CONT)
MALFUNCTION
TEST OR INSPECTION
CORRECTIVE ACTION
ELECTRICAL SYSTEM - CONT
31.
ALL LAMPS DO NOT LIGHT - CONT
Step 2.
Using a multimeter (item 17, appx. B) and semitrailer electrical schematic (figure FO-1) as a guide,
check for ground or open circuit in wiring.
If wiring has a ground or open circuit, repair or replace wiring as required.
32.
ONE OR MORE (BUT NOT ALL) LIGHTS WILL NOT LIGHT
Step 1.
Check for defective light assembly.
Repair or replace defective light assemblies (para. 4-24 thru 4-29).
Step 2.
Using an electrical tester (multimeter) (item 17, appx. B) and semitrailer electrical schematic (figure
FO-1) as a guide, remove tractor intervehicle connectors and check semitrailer connectors J1 and J2
at gooseneck component assembly (para. 4-22).
a. At connector J1, using a multimeter on lowest ohm setting, connect common lead to ground. At
connector, probe pins A, B, C, E, F, and H. Results should reflect greater than 3 ohms. Probe
pins K, L, M, and N. Results should reflect open circuit. Probe pin D. Results should reflect
ground.
b. At connector J2, using a multimeter on lowest ohm setting, connect common lead to ground. At
connector, probe pins 2 thru 5. Results should reflect 1 ohm or greater. Probe pin 1. Results
should reflect ground. Probe pins 6 and 7. Results should reflect open circuit.
Step 3.
Check for broken wires and corroded and loose connections.
a. If connections are loose, tighten connections.
b. If connections are corroded, clean connectors as required or if wires are broken, repair lead wires
as required.
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