| Malfunction | Cause analysis | Troubleshooting |
| Lifting crawl | Insufficient hydraulic fluid. There is air in the hydraulic system. | Add enough hydraulic oil. Lift the cylinder to exhaust. |
| The fork does not rise | No hydraulic oil; the oil is not clean; or there is debris. | Add hydraulic oil, clean the hydraulic mechanism and re-add clean hydraulic oil to remove dirt or change cleaning oil. |
| Add hydraulic oil, clean the hydraulic mechanism and re-add clean hydraulic oil to remove dirt or change cleaning oil. | There is debris and obstacle in the roller or bearing. The unloading oil line is blocked. | There is debris and obstacle in the roller or bearing. The unloading oil line is blocked. |
| There is debris and obstacle in the roller or bearing. The unloading oil line is blocked. | The power cord is disconnected. The battery voltage is too low. The motor carbon brush is damaged. | Connect the power cord. Charge it. Replace the motor carbon brush. |
| Low battery voltage | Insufficient charge; the electrolyte level is too low. The battery is damaged. | Top-up electricity. Add distilled water. Replace the battery. |