TM 5-3805-258-24-1OPERATOR’S STATIONINDIVIDUAL CIRCUIT DESCRIPTIONSYSTEMS OPERATIONSERVICE METERThe machines have a 3T8325 Electronic Service Meter. The meter gets itspower from the 10 amp fuse marked “HR METER & START AID” on thefuse panel under the instrument panel. There is a normally open Start Protectand Service Meter Relay that makes a ground for the meter. When the engineis running and the alternator “R” terminal supplies +12V, the relay closesand activates the service meter.This service meter uses a solid-state (no moving parts) timing circuit thatsends a timing pulse (current for a short time) every 36 seconds to the solenoidthat moves the counter. When the engine is started and the meter first getspower, it takes a minute or more for the first movement of the counter. Themeter works on a 24 volt negative ground system only.The 3T8325 Electronic Service Meter has a very good service record. Ifthe meter does not work, make sure the PU wire has 24 volts and that theLTGR wire is at ground. Most meter failures are really failures of the servicemeter relay that makes the ground for the circuit, or of the wiring to the meter.SERVICE METER1. Service meter.3-174
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business