DiagnosticsHigh severity

Bobcat D3907 (39-07) Fault Code: Left CAN Joystick Y-axis Not in Neutral

Also shown on the panel as 39-07 · Also called Left CAN Joystick Y Axis Not in Neutral, Left CAN Joystick Y-Axis Not in Neutral, Left CAN Joystick Y-axis Not In Neutral, Left Joystick Y-Axis Not in Neutral

Left CAN Joystick Y-axis Not in Neutral · ai-assisted, editor-reviewed · Last updated 2026-07-13

TL;DR

D3907 sets when the Bobcat Drive/Drive Plus controller detects the left joystick Y-axis is out of neutral while PTOL (power take-off left, drive enable) is active. The controller disables drive functions until the joystick shows neutral and the fault clears. Panel form: 39-07.

High severity. Drive functions are disabled as soon as this code sets, which stops machine travel. It's not a code to ignore since the machine can't be driven safely until it's resolved, but it isn't an engine or structural damage risk by itself.

What does Bobcat error code D3907 mean?

Code D3907 means the Drive/Drive Plus controller has seen the left joystick's Y-axis signal reporting a position outside of neutral at a time when PTOL is enabled, meaning the operator has commanded (or the system believes the operator has commanded) a drive input when the machine expects the joystick to be centered.

Because a joystick stuck or reading out of neutral could mean an uncommanded drive movement, the controller responds by disabling drive functions entirely until the fault is resolved and cleared. This is a safety interlock, not a nuisance shutdown.

This code applies to the left joystick's Y-axis (fore-aft, or the drive-direction axis depending on machine configuration) specifically, and is tied to the CAN-based joystick input reporting to the Drive/Drive Plus controller.

Common causes of D3907

Rubber boot on the left joystick installed incorrectly (the part number inside the boot must face the front of the machine) or physically holding the joystick out of neutral, or the operator holding the joystick out of neutral
Left joystick base fault
Drive/Drive Plus controller fault
Moisture, corrosion, or pushed-back pins in the left joystick assembly or in the AWS/SJC harness connectors
Intermittent causes that may not be found at the time of testing, including loose connections, corrosion, pushed-back pins, the controller, the wire harness, or a combination of these

How to troubleshoot Bobcat D3907: first checks

Confirm the key switch (run/enter) is on, the engine is running, and PTOL is enabled, since these are the conditions under which the code sets
Visually inspect the rubber boot on the left joystick and confirm the part number marking inside the boot faces the front of the machine; a boot installed backwards or pinched can hold the joystick off-center
With the machine safely shut down and secured, check that nothing is physically holding the left joystick out of neutral, including debris, a stuck boot, or an operator resting a hand/object on it during startup
Inspect the left joystick base and its wiring for visible damage
Inspect the left joystick assembly connectors and the AWS/SJC harness connectors for moisture, corrosion, or pushed-back (backed-out) pins
If operating with radio remote control, use the diagnostic software's Diagnostics / Radio Remote Control Diagnostics menu to verify correct operation of the left joystick before assuming a hardware fault
If the fault is intermittent and not present during testing, wiggle-test connectors and harness runs near the left joystick assembly and AWS/SJC connectors, since loose connections and pushed-back pins are common intermittent causes

How the code clears

The listed condition for clearing this code is simply that PTOL is enabled once the repair is complete. In practice this means the left joystick must be confirmed in neutral (boot correctly oriented, no obstruction, connectors clean and seated) and PTOL enabled again so the controller can verify normal neutral reporting and drop the fault.

Affected models and serial ranges

D3907 appears in our records across 16 Bobcat models. Match your machine by model and serial number.

Model	Serial ranges
S510	SN A3NJ11001-99999, SN A3NK11001-99999, SN ATZC11001-ATZC99999
S530	SN A7TV11001-99999, SN ATZD11001-99999
S550	SN A3NK11001-A3NL99999, SN A3NM11001-99999
S570	SN A7U711001-799999, SN A7U811001-899999
S590	SN ANMN11001-99999, SN ANMP11001-99999
S630	SN A3NT12370-99999, SN A3NU11001-11111, SN A3NU11112-99999
S650	SN A3NV11001-13098, SN A3NV13099-99999, SN A3NW11001-11248
S750	SN A3P211001-299999
S770	SN A39511001-99999, SN A3P411001-99999
T550	SN A7UJ11001-AJZV12276
T590	SN ALJU11001-999999, SN B37811001-999999, SN B3Z711001-999999
T630	SN A7PU11001-11663, SN A7PU11664-99999
T650	SN A3P012214-099999, SN A3P111242-199999
T750	SN ANKA11001-A99999
T770	SN A3P811001-899999, SN A3P911001-999999
T870	SN A3PG11001-99999, SN A3PH11001-99999

Safety-critical: confirm before use

Operating safety: do not keep operating if braking, steering, or drive control is affected. Secure the machine before diagnosis. Thresholds, component locations, wire numbers, fuse locations, and reset procedures can vary by model, configuration, and serial number. Confirm them in the service documentation for your exact machine.

Ask the AI about D3907 Or ask the community in the forum

Frequently asked questions

What does Bobcat code D3907 mean?

It means the Drive/Drive Plus controller detected the left joystick's Y-axis was not in neutral while PTOL was enabled, so it disabled drive functions as a safety measure.

Why did my Bobcat stop driving after this code appeared?

D3907 disables drive functions whenever it's active. This is intentional: the controller won't allow drive movement if it can't confirm the left joystick is centered in neutral.

Can a bad rubber boot on the joystick cause D3907?

Yes. Bobcat specifically notes the rubber boot's part number marking must face the front of the machine. An incorrectly installed or pinched boot can hold the joystick out of neutral and trigger the code.

I'm running the machine with a remote control and got D3907. What should I check?

Use the diagnostic software's Diagnostics / Radio Remote Control Diagnostics menu to verify the left joystick is operating correctly before inspecting wiring or hardware.

The code comes and goes. What's causing that?

Intermittent D3907 faults are often caused by loose connections, corrosion, or pushed-back pins in the left joystick assembly or AWS/SJC harness connectors. The controller and wire harness itself can also be involved, alone or in combination, and the exact cause may not be found unless the fault is active during testing.

How do I clear D3907 after fixing it?

No separate clearing step is listed beyond having PTOL enabled once the repair is complete. Confirm the joystick sits in true neutral and re-enable PTOL to allow the controller to verify the condition has cleared.

Which Bobcat models can show code D3907?

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