figure 12 printed board assemblies 86243 DPA 4120 and DPA 4140 showing the AC fuses F601 and F602
Caution Before opening the appliance, make sure to disconnect the mains and/or battery power source!
Replacing the fuses F502 and F503 (only to be carried out by the experienced service technician!)
The battery fuses F502 and F503 are located on the power supply PCBs 85270 (DPA 4120) and 85268 (DPA 4140) behind the AMP battery connectors (see also figure 10 and/or figure 11). To replace these fuses you have to remove the cover plate of the appliance and afterwards the power supply input PCB 86243 which is mounted to the rear panel of the appliance. Therefore detach the yellow/green cable from the ground-connector on the appliance's rear panel. Pressing the lock-strap of the AMP-connector together, it can be removed without applying any force. Now, you have to remove the three screws marked "A" (refer to the diagram of the appliance's rear panel on page 2) which allows you to twist the power supply input PCB 86243 up. Make sure not to damage any wires or any other parts. The fuses F502 and F503 are now accessible and can be removed. To re-install the power supply input PCB 86243, these steps have to be proceeded in the opposite order. The yellow/green cable has to be reconnected to the ground-connector on the rear panel of the appliance. By pulling the cable make sure that it sits snugly. Then you can re-attach the cover plate of the enclosure.
