Bobcat D7593 (75-93) Fault Code: Unresponsive Right Speed Sensor
Also shown on the panel as 75-93 · Also called Drive Unresponsive Right Speed Sensor
Unresponsive Right Speed Sensor · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
D7593 sets when the drive/drive plus controller sees a joystick command for movement and the right swash plate sensor reading correctly, but gets no signal from the right speed sensor for 18 seconds. It shows on the panel as 75-93 and points to a wiring, sensor, or controller problem on the right-side drive circuit.
High severity. The machine can lose accurate speed feedback on the right drive motor, which affects how the controller manages movement and can cause unexpected or uneven travel behavior. Diagnose before continuing normal operation, especially in tight work areas or on slopes.
What does Bobcat error code D7593 mean?
D7593 is a drive system fault on Bobcat loaders and compact track loaders (wheel and track models). The drive or drive plus controller uses the right speed sensor, along with the right swash plate position sensor, to know how fast the machine is actually moving on that side. When the operator commands movement with the joystick and the swash plate sensor confirms it is in the right position, the controller expects to see a matching speed signal from the right speed sensor.
If that expected speed signal does not show up for 18 seconds, the controller sets D7593 because it can no longer trust the right side speed feedback used for machine movement and speed control.
On wheeled machines, the speed sensor sits in the motor carrier and reads magnets on a rotating disk. On track machines, the sensor sits in the drive motor and reads teeth on a metal sprocket. Either way, the sensor's job is the same: tell the controller how fast that side of the machine is turning.
What triggers a Bobcat D7593 code?
The code sets when the key switch or run/enter switch is on, Press To Operate Loader (PTOL) is enabled, the engine is running, and there is an active drive command from the joystick while the right swash plate sensor shows correct position but the right speed sensor reports no speed for 18 seconds.
Common causes of D7593
- Open supply wire, ground wire, or signal wire between the speed sensor and the controller (wire numbers vary by model/harness variant, including 1530/5870 supply, 2570/2870 ground, and 3000/3070/3870/3875 signal circuits).
- Metal particles built up on the speed sensor tip or on the magnetic disc (wheel machines) or sprocket area (track machines), blocking a clean reading.
- A failed or worn wheel/track speed sensor, or damage to the magnetic disc or sprocket it reads.
- A fault in the drive/drive plus controller itself.
- Moisture, corrosion, or pushed-back pins in the drive/drive plus controller connector, the speed sensor connector, or any connector along the wire harness.
- An intermittent condition: if the code is not active at the time of testing, the root cause may not show up immediately. Likely culprits in these cases are loose connections, corrosion, pushed-back pins, the controller, the harness, or some combination of these.
How to troubleshoot Bobcat D7593: first checks
- Confirm the machine meets the code's active conditions (key/run switch on, PTOL enabled, engine running, joystick commanding drive) so you can reproduce and verify the fault.
- Inspect the right speed sensor and its mounting area for metal particles, debris, or physical damage to the magnetic disc or sprocket teeth.
- Check the speed sensor connector and the drive/drive plus controller connector for moisture, corrosion, or pins that have pushed back out of place.
- Trace the supply, ground, and signal wires for that sensor circuit for opens, chafing, or damaged insulation, checking connectors along the full harness run.
- If everything checks out visually and electrically but the code was intermittent, treat loose connections, corrosion, or a marginal controller as suspects and recheck after cleaning and reseating connectors.
How the code clears
Bobcat lists cycling power as the step to clear D7593 once the repair is complete. There is no separate reset procedure listed beyond turning the machine off and back on after the fix is made.
Affected models and serial ranges
D7593 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 |
Frequently asked questions
What does Bobcat code D7593 mean?
It means the drive/drive plus controller commanded movement, confirmed the right swash plate sensor was in the correct position, but got no reading from the right speed sensor for 18 seconds. The controller can't verify actual right-side speed, so it flags D7593.
What is the panel display number for D7593?
On the operator panel this code shows as 75-93.
Will D7593 stop the machine from driving?
The listed information describes it as a feedback fault rather than a full shutdown code, but because it affects speed detection on one drive side, you should diagnose it before relying on normal drive performance, particularly in close quarters or on grades.
Is this a wheel machine or track machine fault?
It applies to both. On wheeled Bobcat loaders the sensor is in the motor carrier reading magnets on a rotating disk. On track machines the sensor is in the drive motor reading teeth on a metal sprocket.
What usually causes D7593?
Common causes include open supply, ground, or signal wiring to the right speed sensor, metal debris on the sensor or magnetic disc, a failed sensor, moisture or corrosion in connectors, pushed-back pins, or a controller fault.
How do I clear D7593 after fixing it?
Cycle the key power off and back on. That is the only clearing step listed for this code.
The code won't come back when I test it. What should I check?
That points to an intermittent issue. Focus on loose connections, corrosion, pushed-back pins in connectors, harness damage, or a marginal controller, since these can cause a fault that isn't present at the moment of testing.