REAR MARKER LIGHT(S) DO NOT OPERATE (S/N YB6122 075 AND UP). -725550268

TM 9-2330-385-14

4-13. 24 VOLT ELECTRICAL SYSTEM TROUBLESHOOTING PROCEDURES (CONT).

13. REAR MARKER LIGHT(S) DO NOT OPERATE (S/N YB6122 075 AND UP).

INITIAL SETUP

Tools and Special Tools

References

Tool Kit, General Mechanic's: Automotive

TM 9-2320-364-10

(Item 50, Appendix J)

Equipment Condition

Multimeter (Item 28, Appendix J)

Engine OFF, (TM 9-2320-364-10)

24 vdc cable assembly connected to truck,

Personnel Required

Two

(Para 2-9)

Parking brake applied, (TM 9-2320-364-10)

Wheels chocked, (TM 9-2320-364-10)

NOTE

The following troubleshooting procedures cover the left rear side marker light, but they apply to all rear

marker lights.

All electrical wires and components listed in this troubleshooting procedure are illustrated and located in FO-1.1.

START

KNOWN INFO

TEST OPTIONS

Truck electrical system OK.

Visual inspection.

Does at least one rear side or

All other trailer lights operate.

rear marker light operate?

REASON FOR QUESTION

POSSIBLE PROBLEMS

If no rear side or rear marker

Wire 1012B faulty.

lights operate when power is

Wire 1435 faulty.

applied, fault is trailer main wire

Rear marker light faulty.

harness 1012B. If at least one

rear side or rear marker light

operates, fault is from rear

junction box through rear side

marker light.

Repair wire 1012B

(see schematic, Fig

FO-1.1) or replace

trailer main wire har-

ness (para 4-30.1).

Verify repair, go to

Step 4 of this Fault.

YES

4-118.8