8 Troubleshooting & Maintenance
4
）
If everything is perfectly fine, but the problem persists, replace the control unit;
5
）
Contact the relevant technical personnel if the above doesn’t solve the problem.
5. Maintenance (Take ZK-D4330 as an example)
5.1 Clean the surface of the machine regularly
Use a smooth cleaning cloth with some industrial alcohol to clean the surface of the control unit, crossbars, and the
surfaces of the entire device.
5.2 Replacement of the control unit
When the performance of the WTMD is abnormal, and when you confirm that it is the control unit causing
problems after troubleshooting, you need to replace it following the steps below.
①
Remove the crossbar at the front, then pull the signal cable out.
②
Hold the control unit with one hand, then remove the two bolts at the back of it with another hand. Separate
the crossbar at the front and the control unit.
