Mantis Fault Code
Free · no signupOver-Hoist (ATB)
Winch stops hoisting; Boom cannot telescope out; Alarm active.
System
General LMI
Symptom
Winch stops hoisting; Boom cannot telescope out; Alarm active.
Diagnosis & fix steps
Anti-Two Block (ATB) Circuit Open.
LOGIC: The safety loop is broken. The weight has either been lifted by the hook block, or the wire is broken.
ACTION: 1. Ensure the ATB weight is hanging free.
2. Check the "dead-end" wire on the boom tip.
FIX: Repair the broken ATB wire or replace the microswitch in the boom-tip box.
Red Seal field insights
On Mantis telescopic booms, the ATB wire is often on a "Reeling Drum." If the spring in that drum is weak, the wire will slack and get caught in the boom sections as you retract, snapping the wire. Keep that reel tensioned!
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
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- Error 01All crane functions (hoist, telescope, boom down) are cut off; Audible alarm.
- Code 10LMI screen displays "Communication Error"; All safety lockouts active.