Stop Code “BA” Alert: Troubleshooting the ZF Filter Clogged Alarm and Sourcing the Correct Sensor
Introduction: Decoding the “BA” Fault


The “BA” fault code or the FILTER CLOGGED ALARM on ZF transmissions is a direct warning to the operator that the fine filter (pressure filter) is blocked. Ignoring this can cause the 16+2 bar system pressure to drop, resulting in clutch slippage and pump damage.
This technical guide, informed by Tianjin XiaoHang Construction Machinery Co., Ltd.’s 20 years of expertise, explains this fault and the necessary parts procurement.
Section 1: The Alarm Mechanism and Diagnosis
The Role of the Pressure Drop Switch
The alarm is triggered by the Pressure Drop Switch (PRES. DROP SWITCH) , which is often a CLOSING SWITCH that closes the circuit when the pressure differential across the filter (e.g., 0750.131.053) exceeds a limit.
- Action: The first step is always to replace the filter immediately. If the alarm persists, the fault is likely the TAPPET SWITCH 0501.210.966 or its wiring.
Section 2: Sourcing Verified Filter Kits and Sensors
The XiaoHang Quality Standard
When addressing the “BA” alarm, two parts must be sourced correctly:
- The Filter: Must be a high-quality replacement filter (e.g., 0501.333.764 for 6WG191) that guarantees optimal flow.
- The Switch: If the alarm is persistent, the TAPPET SWITCH 0501.210.966 must be replaced to ensure the alarm accurately reports the status.
Conclusion: Immediate Action is Required
Don’t ignore the “BA” code. Trust XiaoHang Machinery Co. to supply the correct filter and pressure switch components, ensuring rapid maintenance and technical integrity.
| Contact Detail | Information |
| Sales Representative | Tony Chang |
| Trading Entity | TIANJIN LINKWORLD TRADING CO. LTD |
| Direct Contact (Phone/WhatsApp) | +86 15822863467 |
| 5858518@gmail.com | |
| Expertise Provided by | Tianjin XiaoHang Construction Machinery Co., Ltd. |