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Bobcat M1122 (11-22) Fault Code: Seatbar Sensor Out of Range Low

Also shown on the panel as 11-22 · Also called Seat Bar Sensor Out of Range Low

Seatbar Sensor Out of Range Low · ai-assisted, editor-reviewed · Last updated 2026-07-13

TL;DR

Bobcat fault code M1122, shown on the panel as 11-22, means the gateway controller is not seeing a voltage on the seatbar sensor signal wire (wire 3370 on some models, wire 3920 on others). This is a hall-effect sensor issue, and when it sets, the machine disables drive, lift, and tilt functions until it is resolved.

High severity. M1122 does not damage the machine by itself, but it locks out drive, lift, and tilt functions, so the machine cannot be operated until the fault is cleared. Treat it as a stop-work code.

What does Bobcat error code M1122 mean?

M1122 is a Bobcat gateway controller code that fires when it cannot detect a voltage on the seatbar sensor's signal wire. Depending on the model, that signal wire is either wire 3370 or wire 3920. The seatbar sensor is a hall-effect sensor, powered with 5 volts from the gateway controller on a supply wire (wire 5370 or wire 3900 depending on model), and it returns a voltage on the signal wire that corresponds to the physical position of the seatbar.

When the controller sees no voltage on that signal wire, it assumes the seatbar position cannot be trusted, and as a safety measure it disables drive, lift, and tilt functions. This is by design: the seatbar is part of the operator presence and restraint system, so the machine will not let you move it or run hydraulics if it cannot confirm the bar's state.

This code is set with the key switch in the run/enter (on) position. There is no engine-running or load requirement noted beyond that: the controller checks for the sensor signal any time the key is on.

Common causes of M1122

  • 5-volt supply wire (5370 or 3900) or the signal wire (3370 or 3920) shorted to ground.
  • Faulty seatbar sensor (hall-effect sensor).
  • Faulty gateway controller.
  • Moisture, corrosion, or pushed-back pins in the gateway controller connectors, seatbar sensor connector, mainframe harness, or cab harness.
  • Intermittent wiring or connector issues, loose connections, or a combination of these problems that may not be found if the code is not active during testing.

How to troubleshoot Bobcat M1122: first checks

  1. Check the seatbar sensor connector and the cab harness/mainframe harness connectors for moisture, corrosion, or pushed-back pins.
  2. With the key on, verify the 5 volt supply is present at the sensor's supply wire (5370 or 3900 depending on model) and that it is not shorted to ground.
  3. Check the signal wire (3370 or 3920 depending on model) for a short to ground along its length between the sensor and the gateway controller.
  4. Inspect the seatbar sensor itself for damage or failure, since it is a hall-effect sensor that can fail internally.
  5. If the code is not currently active, treat it as intermittent: recheck all connectors and harness routing for loose pins or chafing, since the cause may not show up during static testing.

How the code clears

Once the repair is complete, cycle power (turn the key off and back on) to clear the code. No separate clearing procedure is listed beyond a power cycle.

Affected models and serial ranges

M1122 appears in our records across 16 Bobcat models. Match your machine by model and serial number.

ModelSerial ranges
S510SN A3NJ11001-99999, SN A3NK11001-99999, SN ATZC11001-ATZC99999
S530SN A7TV11001-99999, SN ATZD11001-99999
S550SN A3NK11001-A3NL99999, SN A3NM11001-99999
S570SN A7U711001-799999, SN A7U811001-899999
S590SN ANMN11001-99999, SN ANMP11001-99999
S630SN A3NT12370-99999, SN A3NU11001-11111, SN A3NU11112-99999
S650SN A3NV11001-13098, SN A3NV13099-99999, SN A3NW11001-11248, SN A3NW11249-99999
S750SN A3P211001-299999
S770SN A3P411001-99999
T550SN A7UJ11001-AJZV12276
T590SN ALJU11001-999999, SN B37811001-999999, SN B3Z711001-999999
T630SN A7PU11001-11663, SN A7PU11664-99999
T650SN A3P012214-099999, SN A3P111242-199999
T750SN ANKA11001-A99999
T770SN A3P811001-899999, SN A3P911001-999999
T870SN A3PG11001-99999, SN A3PH11001-99999

Frequently asked questions

What does Bobcat code M1122 mean?

It means the gateway controller cannot detect a voltage on the seatbar position sensor's signal wire. The seatbar sensor is a hall-effect sensor that reports the bar's position, and when its signal goes missing, the controller flags M1122 and locks out drive, lift, and tilt.

Can I still operate the machine with M1122 active?

No. When M1122 is set, the machine disables drive, lift, and tilt functions as a safety precaution, so you will not be able to operate it until the fault is diagnosed and cleared.

Why does M1122 show different wire numbers on different machines?

Bobcat uses two wiring variants across its skid-steer and compact track loader lineup. Some models use supply wire 5370 and signal wire 3370, while others use supply wire 3900 and signal wire 3920. Both variants are the same fault, just on different harness numbering.

What is the panel number for M1122?

On the numeric display, M1122 shows as 11-22.

How do I clear M1122 after fixing it?

Cycle the key switch off and back on. That is the only clearing step listed for this code; there is no separate reset procedure.

What if the code doesn't show up when I test it?

If M1122 is intermittent and not active during testing, the cause may not be immediately found. Suspect loose connections, corrosion, or pushed-back pins in the connectors and harness, and inspect them carefully even without an active fault.

What systems are affected besides the seatbar itself?

The gateway controller ties the seatbar sensor into drive, lift, and tilt lockouts, so a bad sensor signal affects far more than just the seat area. This is why the code is treated as a stop-work issue rather than a minor warning.