USED, TAKE OFF - ELECTRONIC CONTROL BOX FOR M939 SERIES - 12450333
USED, TAKE OFF - ELECTRONIC CONTROL BOX FOR M939 / M923 SERIES VEHICLES. THIS CONTROL BOX GIVES YOUR TRUCK REVERSE POLARITY PROTECTION, IT CONTROLS YOUR ALTERNATOR OUTPUT ON THE 60 AMP ALTERNATORS, CONTROLS THE POWER TO YOUR STARTER SOLENOID, AND IT ALSO LOCKS OUT THE STARTING CIRCUIT WHEN YOUR TRANSMISSION IS NOT IN NEUTRAL. THIS IS A COMPLETE ASSEMBLY, YOU JUST BOLT IT ON AND PLUG IT IN. IMPROPER SHUT DOWN OF YOUR TRUCK CAN DAMAGE THESE CONTROL BOXES. YOU MUST FIRST TURN OFF THE IGNITION SWITCH UNTIL THE ENGINE IS NO LONGER SPINNING, AND THEN IT IS SAFE TO TURN OFF THE BATTERY SWITCH. NOT FOR M809 SERIES TRUCKS PART # 12450333 NSN 6110014442546, NSN 6110011448674. OTHER NUMBERS INCLUDE 11669304, WSU4003UT, SX75G3.