Bobcat D7575 (75-75) Fault Code: Left Wheel Speed Uncommanded Motion
Also shown on the panel as 75-75 · Also called Drive Left Wheel Speed Uncommanded Motion
Left Wheel Speed Uncommanded Motion · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
D7575 (panel code 75-75) sets when the drive/drive plus controller sees pulses from the left speed sensor while the joysticks and swash plates are sitting in neutral. The controller reads this as the machine moving when it should not be, and it shuts the engine down. It shows up on Bobcat skid-steer and compact track loader models including the S510 through S770 and T550 through T870 lines.
High severity. The controller shuts the engine down when this code sets, which stops work immediately. It is not a code to keep running through, but it is not an immediate safety-of-life emergency like a hydraulic or lifting failure, so it lands at High rather than Critical.
What does Bobcat error code D7575 mean?
D7575 is a left wheel (or left track drive motor) speed sensor code. The drive/drive plus controller uses the left speed sensor to track machine movement and ground speed. When the joysticks are centered and the swash plates are in neutral, the controller expects zero pulses from that sensor. If it sees pulses anyway, it interprets this as uncommanded motion, meaning the machine appears to be moving when no drive command has been given.
Because uncommanded motion is a safety-related condition, the controller responds by shutting the engine down rather than letting the machine continue to operate.
On wheeled machines, the left speed sensor is located in the motor carrier and reads magnets on a rotating disk. On track machines, the sensor is in the drive motor and reads the teeth on a metal sprocket. The underlying logic is the same for both, only the sensing hardware differs.
Common causes of D7575
- Rub through on the AWS/SJC wire harness, which can let wires short or cross-talk and send false pulses to the controller.
- A faulty left wheel speed sensor sending signal pulses even though the machine is not moving.
- A fault in the drive/drive plus controller itself.
- A problem with the hydrostatic pump.
- Moisture, corrosion, or pushed-back pins in the drive/drive plus controller connector 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 problems.
How to troubleshoot Bobcat D7575: first checks
- Confirm the key switch/run-enter switch is on, PTOL is enabled, and the engine is running, since these are the conditions under which the code can set.
- Inspect the AWS/SJC wire harness for rub-through spots, especially anywhere it contacts frame edges, brackets, or moving parts.
- Check the drive/drive plus controller connector and the AWS/SJC harness connectors for moisture, corrosion, or pins that have been pushed back out of their sockets.
- Inspect the left wheel speed sensor and, on wheeled machines, the magnets on the rotating disk in the motor carrier; on track machines, check the teeth on the metal sprocket at the drive motor.
- With joysticks in neutral and swash plates in neutral, look for any signal activity coming from the left speed sensor circuit that shouldn't be there.
- If the code was intermittent and is not present during testing, recheck all connections since the cause may not show up until conditions repeat.
How the code clears
Cycle the key power off and back on after completing repairs. No separate clearing step is listed beyond cycling power.
Affected models and serial ranges
D7575 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 D7575 mean?
It means the drive/drive plus controller detected pulses from the left wheel or left track speed sensor while the joysticks and swash plates were in neutral. The controller treats this as uncommanded motion and shuts the engine down.
Why did my Bobcat shut off when D7575 appeared?
The engine shutdown is part of how the controller responds to this code. It is a built-in safety response to what looks like unexpected machine movement, not a separate malfunction.
Is D7575 the same on skid-steers and track loaders?
The logic is the same, but the hardware differs. Wheeled machines have the sensor in the motor carrier reading magnets on a rotating disk, while track machines have the sensor in the drive motor reading teeth on a metal sprocket.
What is the AWS/SJC harness that keeps getting mentioned?
It's the wire harness tied to the drive system's speed sensing and joystick control circuits. A rub-through on this harness is listed as one of the possible causes of D7575.
How do I clear D7575 after fixing it?
Cycle the key power off and back on. No other clearing procedure is listed for this code.
What if the code doesn't show up when I test the machine?
If D7575 was intermittent, the cause may not be found during that test session. Likely candidates in that case are loose connections, corrosion, pushed-back pins, the controller, or the wire harness, alone or in combination.
Which Bobcat models can throw a D7575 code?
It affects models including the S510, S530, S550, S570, S590, S630, S650, S750, S770, and the T550, T590, T630, T650, T750, T770, and T870.