TM-9-2320-361-24-1

2-1/2 TON, 6X6, M44A2 SERIES TRUCKS

TECHNICAL MANUAL; FIELD AND SUSTAINMENT MAINTENANCE PART 1 OF 2

AUGUST 2006

TM-9-2320-361-24-1 - Page 234 of 1176

TM 9-2320-361-24-1

0013 00

0013 00-22

LIGHTING AND WIPER SYSTEM TROUBLESHOOTING (Contd)

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

ONE OR MORE

TRAILER LIGHTS

INOPERATIVE

NOTE

For stoplight circuit test, brake pedal

must be depressed and air pressure

maintained.

Test 1. Test trailer receptacle voltage.

1. Place main light switch lever

in position corresponding to

inoperative lamp.

2. Set multimeter to voltage

range that will measure

24 VDC.

3. Connect negative lead of

multimeter to trailer receptacle

pin D. Touch positive lead to

appropriate trailer receptacle

pin of circuit being tested.

Light switch must be in

corresponding position.

Test 2. Test trailer receptacle ground.

1. Set multimeter to RX 1 scale.

2. Connect negative lead of

multimeter to frame ground.

Touch positive lead to pin D of

trailer receptacle.

1. If battery voltage is present,

disconnect and reconnect male

connector to ensure positive

connection. If trailer lamps still do

not light, check trailer lighting

system.

2. If battery voltage is not present at

one or more of the pins being tested,

continue with test 2.

If continuity is not present, repair or

replace lead 90 (WP 0090 00).

Table 4. Trailer Connection System Troubleshooting Procedures.

H

G

D

C

E

B

F

A

L

K

N

J

M

H

C

A

B

E

F

D

INTAKE FUEL PUMP

FUEL TANK SENDING UNIT

90

490

B.O. CLEARANCE

489

CLEARANCE

REAR

HARNESS

TRAILER

RECEPTACLE