TM 10-3930-641-20
ELECTRICAL SYSTEMS TROUBLESHOOTING (CONT)
(Sheet 1 of 2)
PROBLEM NO. 30
ALARM
BACKUP ALARM DOES NOT WORK
POWER switch ON. TRANSMISSION GEAR SELECTOR in REVERSE. Ceiling heater
blower motor works (see NOTE).
NOTE
If ceiling blower motor does not work, problem is at 15 amp. Circuit Breaker (CB) or associated wiring.
The backup alarm receives its power from 15 amp. CB (12, page 2-70). POWER switch must be ON to energize main power relay connecting battery
voltage to the 15 amp. CB.
Placing transmission selector in reverse closes micro-switch on the transmission interlock, which sounds the backup alarm.
