TM 5-3805-262-203-24. ACCESSORIES TROUBLESHOOTING (CONT)MALFUNCTIONTEST OR INSPECTIONCORRECTIVE ACTION9. BOTH REAR DEFOGGER FANS DO NOT OPERATE (Cont).Step 3.Remove engine left side panels (page 9-14).Connect multimeter across terminals of cab 30 ampere circuitb r e a k e r.3-174Multimeter should indicate zero.a. If multimeter indicates 24 volts, circuit breaker is open. Go tostep 4 below.b. If multimeter indicates zero, replace cab relay (page 5-26).Step 4.Disconnect battery ground cable (page 5-148).Disconnect wire connected between cab relay BAT. terminal and cab 30ampere circuit breaker long, silver terminal.Reconnect battery ground cable.Connect multimeter between long, silver terminal of cab 30 amperecircuit breaker and chassis .Multimeter shall indicate 24 volts.a. If multimeter indicates zero, replace cab 30 ampere circuitbreaker (page 5-26).b. If multimeter indicates 24 volts, a short circuit to grounde x i s t s i n c a b e l e c t r i c a l c i r c u i t . I s o l a t e d e f e c t i v e c i r c u i t byreconnecting wire from cab relay BAT. terminal to long, silverterminal of cab circuit breaker. Then, at cab switch panel,disconnect and tape wires connected to each of the three circuitbreakers one at a-time and check if remaining circuit(s) operatewhen associated switch is operated.
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business