TM 1-1740-221-13&P&P
FIELD MAINTENANCE
CHASSIS ELECTRICAL TROUBLESHOOTING
INITIAL SETUP:
Test Equipment
Multimeter (, WP 0127)
Tools and Special Tools
General Mechanic Tool Box (, WP 0127)
Personnel Required
91B Light Wheel Vehicle Mechanic (2)
References
TROUBLESHOOTING PROCEDURE
CHASSIS ELECTRICAL Troubleshooting Procedures
WARNING
Do not attempt to service or otherwise make any adjustments, connections, or re-connections
of wires until SATS is shut down and batteries are disconnected. Remove all rings, watches,
and other jewelry when performing maintenance on this equipment.
The use of Personal Protective Equipment (PPE) is required when using or handling hazardous
materials associated with operating and maintaining equipment (jet fuel, hydraulic luid, brake
luid, ethylene glycol, cleaning solvents, compressed air, and engine/axle oil). Failure to use
PPE when handling these materials could result in injury or death.
BRANCH 1.
HORN INOPERATIVE
1. Set brakes and chock vehicle. Turn Ignition switch on and check for 12 volts at wire 91 (FO-1, Line 51)
at the horn (WP 0128).
CONDITION/INDICATION
Is 12 volts present?
DECISION
YES Proceed to Step 2.
BRANCH 2.
2.
Disconnect wire 2 (FO-1, Line 51) at the horn (WP 0128) and ohms check from wire 2 to ground with the
horn button depressed.
CONDITION/INDICATION
Does circuit have continuity?
00111