Bobcat H2306 (23-06) Fault Code: Rear Base Solenoid Short to Ground
Also shown on the panel as 23-06 · Also called Rear Base Output Short to Ground, Rear Base Solenoid Short To Ground, Rear Base Solenoid Short to Ground
Rear Base Solenoid Short to Ground · ai-assisted, editor-reviewed · Last updated 2026-07-13
TL;DR
H2306 (panel form 23-06) sets when the auxiliary controller commands the rear base solenoid but does not detect voltage on signal wire 4440 or return wire 2440. The rear base function is disabled until the fault is fixed and power is cycled.
Medium severity. The rear base auxiliary hydraulic function is disabled until this is repaired, which stops attachments that rely on that circuit from working. It is not an engine or structural safety issue by itself, but a short to ground can also point to chafed harness insulation that deserves prompt attention.
What does Bobcat error code H2306 mean?
H2306 is a Bobcat fault code that fires when the auxiliary controller sends a command to the rear base solenoid but does not see the expected voltage return on signal wire 4440 or return wire 2440. The controller interprets this as a short to ground somewhere in that circuit.
The rear base solenoid is what directs hydraulic flow out through the rear auxiliary female coupler, so it controls attachments plumbed into that port. When the controller sets H2306, it disables the rear base function entirely as a protective measure, rather than letting a shorted circuit keep drawing current or behaving unpredictably.
This code shows up across a wide range of Bobcat skid-steer and compact track loader models, including the S510 through S770 series and the T550 through T870 series, since they share similar auxiliary hydraulic control architecture.
Common causes of H2306
- Signal wire 4440 or return wire 2440 shorted to ground somewhere in the harness.
- A failed rear base solenoid.
- A fault inside the auxiliary controller itself.
- Moisture, corrosion, or pushed-back pins in the auxiliary controller connectors, the rear base solenoid connector, or the mainframe harness connectors.
- Intermittent causes that may not be present 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 H2306: first checks
- Confirm the conditions under which the code sets: key switch in run/enter position, rear auxiliaries enabled, and a rear base command being given. If those three conditions are not all present, the controller will not be evaluating this circuit.
- Visually inspect the auxiliary controller connectors, the rear base solenoid connector, and the mainframe harness connectors for moisture, corrosion, or pins that have been pushed back out of their sockets.
- Check signal wire 4440 and return wire 2440 for chafed insulation, pinch points, or contact with ground anywhere along their run between the controller and the solenoid.
- Test the rear base solenoid itself for an internal short to ground rather than assuming the harness is at fault.
- If the code is not currently active, treat it as intermittent and recheck all connectors and harness routing for loose connections or corrosion that only shows up under vibration or moisture.
How the code clears
Once the wiring, solenoid, connector, or controller issue is repaired, the code is cleared by cycling key power off and back on. No separate clearing step is listed beyond a power cycle.
Affected models and serial ranges
H2306 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 ATZC11001-99999 |
| 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, SN A3NW11249-99999 |
| 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 H2306 mean?
It means the auxiliary controller commanded the rear base solenoid to activate but did not detect the expected voltage on signal wire 4440 or return wire 2440. The controller reads this as a short to ground and disables the rear base function.
What is the panel display number for H2306?
On the numeric panel display, this code shows as 23-06.
Will my attachment still work with H2306 active?
No. Once H2306 sets, the rear base function is disabled, so any attachment relying on the rear auxiliary female coupler and the rear base solenoid will not operate until the fault is repaired.
What usually causes this short to ground?
Common causes include signal wire 4440 or return wire 2440 shorted to ground, a failed rear base solenoid, a fault in the auxiliary controller, or moisture, corrosion, and pushed-back pins in the related connectors. If the fault is intermittent, loose connections or a combination of harness and connector problems can also be responsible.
How do I clear H2306 after repair?
Cycle the key power off and back on. That is the only clearing step listed for this code.
Which Bobcat models can show code H2306?
It appears on Bobcat S510, S530, S550, S570, S590, S630, S650, S750, and S770 skid-steer loaders, and T550, T590, T630, T650, T750, T770, and T870 compact track loaders.
Is H2306 safe to keep operating with?
It disables one auxiliary hydraulic function rather than the whole machine, but a short to ground in the wiring is worth diagnosing promptly since chafed or damaged harness insulation can worsen over time or affect nearby circuits.