TM-9-2320-273-20

TRUCK TRACTOR, LINE HAUL; LIGHT EQUIPMENT TRANSPORTER; TRUCK CHASSIS; MEDIUM EQUIPMENT TRANSPORTER

TECHNICAL MANUAL; ORGANIZATIONAL MAINTENANCE

NOVEMBER 1980

TM-9-2320-273-20 - Page 476 of 1500

TM 9-2320-273-20

Table 5-14. Miscellaneous Electrical Circuit Troubleshooting.

INSTRUCTION

INDICATION

YES

NO

REMARKS

1

ELECTRICAL HORN IS INOPERATIVE

1

Check horn for a good

Clean and tighten.

Go to

Repair.

ground.

Step 2.

2 Check for voltage at

12 volts dc nominal.

Replace

Go to

horn using multimeter

horn

Step 3.

while pressing horn

(para 5-68).

button.

3

Check for voltage at

12 volts dc nominal.

Check cir-

Go to

terminal 3 (fig. 5-38)

cuit 41

Step 4.

on horn relay while

wiring.

pressing horn button.

4

Check for voltage at

12 volts dc nominal.

Go to

terminal 1 on horn

Step 5.

relay while pressing

horn button.

5 Jumper terminal 2 on

Horn operates.

Go to

Replace

horn relay to ground.

Step 6.

horn relay

(para 5-67).

6

Check horn button

Wiring and ground

Replace

Repair.

switch ground and

okay.

button

wiring to horn relay.

switch

(para 5-67).

Figure 5-38. Electric Horn Circuit

I

I

1

1

TA 074723

5-60