Bobcat D7555 (75-55) Fault Code: Right Forward Drive Solenoid Error Off
Also shown on the panel as 75-55 · Also called Drive Right Forward Drive Solenoid Error Off
Right Forward Drive Solenoid Error Off · ai-assisted, editor-reviewed · Last updated 2026-07-21
TL;DR
D7555 (panel code 75-55) sets when the drive/drive plus controller commands the right forward drive solenoid but does not detect voltage through it. The machine drops into speed management mode until the fault is fixed. This is an open-circuit or no-voltage condition on that solenoid's signal path, not a signal-too-high fault.
Medium severity. The machine keeps running but is forced into speed management mode, which limits normal drive performance. It is not an immediate safety shutdown, but reduced drive control on a skid steer or track loader should be diagnosed before continued heavy use.
What does Bobcat error code D7555 mean?
D7555 means the drive/drive plus controller sent a command to the right forward drive solenoid but never saw voltage show up on that circuit. The controller relies on varying voltage to the drive solenoids based on joystick input, so when it commands the solenoid on and gets no voltage feedback, it knows something in that circuit path is not working as expected.
Once this happens, the loader shifts into speed management mode as a protective measure. This keeps the machine operable but limits drive performance until the underlying wiring, solenoid, or controller issue is corrected.
This is an 'off' or no-voltage type error, meaning the circuit is not delivering voltage when it should, so diagnosis should focus on opens, shorts to ground, bad connections, or a failed solenoid/controller rather than a stuck-high voltage condition.
Common causes of D7555
- Signal wire 4260 or ground wire 2660 shorted to ground or open, breaking the circuit path needed for the controller to see voltage at the solenoid.
- Failed right forward drive solenoid that will not pass or hold voltage even when commanded.
- Fault inside the drive/drive plus controller itself.
- Moisture, corrosion, or pushed-back pins in the drive/drive plus controller connectors, the right forward drive solenoid connector, or the AWS/SJC wire harness.
- Intermittent connection problems (loose connections, corrosion, pushed-back pins, harness damage, or a combination) that may not be present at the moment of testing, making the fault harder to isolate.
How to troubleshoot Bobcat D7555: first checks
- Confirm the conditions for the code are present: key switch/run-enter on, PTOL enabled, engine running, and a forward drive command being given, since the controller only checks for solenoid voltage under these conditions.
- Inspect the right forward drive solenoid connector and the drive/drive plus controller connectors for moisture, corrosion, or pins that have been pushed back out of place.
- Check signal wire 4260 and ground wire 2660 for continuity, looking for an open circuit or a short to ground along their length and at connector terminals.
- Inspect the AWS/SJC wire harness for chafing, pinch points, or corrosion that could cause an open or grounded signal path.
- Test the right forward drive solenoid directly to see if it responds to voltage as expected, since a failed solenoid can cause the same no-voltage-detected symptom.
- If the code will not reproduce and was not active during testing, treat it as intermittent and focus on loose connections, corrosion, and pushed-back pins as the most likely culprits.
How the code clears
Cycle power to the machine (key off, then back on) after completing the repair. No separate clearing step is listed beyond cycling power.
Affected models and serial ranges
D7555 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 D7555 mean?
It means the drive/drive plus controller commanded the right forward drive solenoid on but did not detect voltage through it. This puts the loader into speed management mode until the fault is corrected.
Can I keep working with a D7555 code active?
The machine will still run in speed management mode, but drive performance will be limited. It is best to diagnose and repair the issue rather than continuing extended operation with reduced drive control.
What is the numeric panel form of D7555?
On the panel display it shows as 75-55.
How is D7555 different from D7556?
D7555 is the right forward drive solenoid error, while D7556 is the right reverse drive solenoid error. Both involve the same solenoid position (right side) but on opposite drive directions, so check which direction the machine struggles in before assuming which code applies.
Does D7555 always mean the solenoid itself is bad?
No. The listed causes include an open or grounded signal wire 4260 or ground wire 2660, a bad drive/drive plus controller, connector corrosion or pushed-back pins, or a failed solenoid. All of these need to be checked, not just the solenoid.
Why does my Bobcat drop into speed management mode?
Speed management mode is the controller's protective response to a D7555 fault. Since it cannot confirm voltage at the right forward drive solenoid, it limits drive performance rather than allowing uncontrolled or unpredictable operation.
What if the D7555 code won't come back when I test it?
Intermittent D7555 codes may be caused by loose connections, corrosion, pushed-back pins, harness damage, or the controller itself. If the code isn't active during testing, focus inspection on these connection-related issues since they are the most likely intermittent causes.