TM-9-2320-283-20-1

TRUCK TRACTOR, LINE HAUL, 50,000 GVWR, 6X4, M915A1

TECHNICAL MANUAL; ORGANIZATIONAL MAINTENANCE PART 1 OF 3

DECEMBER 1983

TM-9-2320-283-20-1 - Page 394 of 926

TM 9-2320-283-20-1

TROUBLESHOOTING.

2-11. TROUBLESHOOTING PROCEDURES (Continued).

MALFUNCTION

INSTRUCTION

INDICATION

YES

NO

82.

ELECTRICAL HORN NOT WORKING (Continued).

NOTE

With positive lead on circuit 41B-PP (or other suitable hot lead), check ground

with negative lead for steps 6 thru 9.

6.

Remove horn button

(para 3-118), and go

to step 7.

7.

Check for voltage at

12-volts dc

Go to step 8.

Clean horn

horn button plate.

nominal.

button plate.

button (para

3-118).

Install

relay RY-1 and

circuit breaker

bracket (para

3-112 and

3-114).

8.

Check for voltage at

12-volts dc

Install horn

Clean horn

circuit 41C-BK terminal

nominal.

button (para

button contact

at horn button.

3-118), and go

cups.

Install

to step 9.

relay RY-1 and

circuit breaker

bracket (para

3-112 and

3-114).

NOTE

Assistant must press and hold horn button

when doing the following checks.

2-268