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Bobcat M3707 (37-07) Fault Code: Two Speed Secondary Solenoid Open Circuit

Also shown on the panel as 37-07 · Also called Two-Speed Second Output Open Circuit

Two Speed Secondary Solenoid Open Circuit · ai-assisted, editor-reviewed · Last updated 2026-07-13

TL;DR

M3707 (panel form 37-07) sets when the gateway controller detects an open circuit on the two speed makeup solenoid, either signal wire 4360 or return wire 2360. This solenoid feeds charge pressure to the inactive motor pistons when the machine is running in high range. When the code is active, two speed travel is disabled until the fault is fixed and power is cycled.

Medium severity. Two speed travel is disabled while this code is active, which limits machine performance but does not by itself indicate a safety-critical failure. Diagnose it before returning the machine to full duty, especially if high range is needed for the job.

What does Bobcat error code M3707 mean?

M3707 is set by the gateway controller when it sees an open circuit on the two speed makeup solenoid's signal wire (4360) or its return wire (2360).

The two speed makeup solenoid supplies charge pressure to the motor pistons that are not active while the machine runs in high range. It only energizes when the machine is actually in high range, so the fault logic is tied to that operating condition.

When M3707 is active, the controller disables two speed travel as a protective response. This means the machine will be limited to a single speed range until the wiring or solenoid fault is corrected.

Common causes of M3707

  • Signal wire 4360 shorted to supply voltage or open
  • Return wire 2360 open
  • Faulty two speed makeup solenoid
  • Faulty gateway controller
  • Moisture, corrosion, or pushed-back pins in the gateway controller connectors, the two speed makeup solenoid connector, or the mainframe harness
  • Intermittent fault: if the code is not active at the time of testing, the cause may not be found immediately. Probable causes in this case include loose connections, corrosion, pushed-back pins, the controller, the wire harness, or a combination of these

How to troubleshoot Bobcat M3707: first checks

  1. With the key switch/(run/enter) on, check for the code and note whether it is active or stored/intermittent
  2. Inspect the two speed makeup solenoid connector and the gateway controller connectors for moisture, corrosion, or pushed-back pins
  3. Trace signal wire 4360 for an open circuit or a short to supply voltage
  4. Trace return wire 2360 for an open circuit
  5. Inspect the mainframe harness along the routing to the solenoid and controller for chafing, pinches, or loose connections
  6. If the code is intermittent, wiggle-test connectors and harness sections while watching for the code to reset, since the fault may not show up on a static check

How the code clears

Cycle power (turn the key switch off, then back to run/enter) after completing the repair. No separate clearing step is listed beyond cycling power.

Affected models and serial ranges

M3707 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 M3707 mean?

It means the gateway controller has detected an open circuit on the two speed makeup solenoid's signal wire (4360) or return wire (2360). This solenoid supplies charge pressure to inactive motor pistons while the machine is in high range.

Why does M3707 disable two speed?

The controller disables two speed travel as soon as it sees the open circuit, because the makeup solenoid cannot be verified to work correctly in high range. This is a protective step, not a separate mechanical failure.

What is the panel display code for M3707?

On the numeric panel display, M3707 shows as 37-07.

Can M3707 be intermittent?

Yes. If the code is not active when you test the machine, the root cause may not be found right away. Likely culprits in intermittent cases are loose connections, corrosion, pushed-back pins, the controller, or the wire harness, or some combination of these.

Which Bobcat models can show code M3707?

This code applies to the S510, S530, S550, S570, S590, S630, S650, S750, S770, T550, T590, T630, T650, T750, T770, and T870 models.

How do I clear M3707 after a repair?

Cycle power by turning the key switch off and back to run/enter. No other clearing procedure is listed for this code.

Does M3707 only appear in high range?

The two speed makeup solenoid only energizes when the machine is in high range, so the open circuit that triggers M3707 is tied to that operating mode. The condition for the code itself is simply key switch/(run/enter) on.