4-14. 12-VOLT ELECTRICAL SYSTEM TROUBLESHOOTING PROCEDURES (CONT).
3. REAR MARKER LIGHT(S) DO NOT OPERATE.
Tools and Special Tools
Tool Kit, General Mechanic's: Automotive
(Item 50, Appendix J)
Multimeter (Item 28, Appendix J)
Engine OFF, (TM 9-2320-364-10)
Wheels chocked, (TM 9-2320-364-10)
12 vdc cable assembly connected to truck,
Parking brake applied, (TM 9-2320-364-10)
The following troubleshooting procedures cover one rear marker light, but they apply to all three rear marker lights.
All electrical wires and components listed in this troubleshooting procedure are illustrated and located in FO-1.
Truck electrical system OK.
Does at least two rear marker
All other trailer lights operate.
lights operate when power is
REASON FOR QUESTION
If no rear marker lights operate,
Wire 1435-34 faulty.
fault is in wire 1435-34. If at
Light lamp faulty.
least two rear marker lights
Marker light faulty.
operate, fault is between wire
Wire 1012-31 faulty.
1012-31 and faulty light lamp.
Repair wire 1435-34
(see schematic, Fig
FO-1) or replace rear
harness (Para 4-30).
Verify repair, go to
Step 7 of this Fault.