The service manuel is very helpful, we where able to restore the device to its working operation again.
Text excerpt from page 10 (click to view)
- When using Ni-Cd batteries (250 mAh): Talk time: 4hrs approx. Standby time: 40hrs approx. (Times indicated are for peak performance) - The batteries reach peak performance after several full charge/ discharge cycles. - The batteries cannot be overcharged unless they are repeatedly removed and replaced. - If battery life is shortened then please check that battery and charge terminals are clean. - For maximum battery life, it is recommended that the handset is not recharged until battery icon flashes 4.4. Replacing the Batteries
If the icon flashes after a few telephone calls even when the handset batteries have been fully charged, 2 batteries must be replaced. Charge new batteries for approximately 7 hours before initial use. (The telephone line cord must not be connected to the telephone socket at this time). When replacing the batteries, ensure that the correct battery type is selected.
- To exit the operation, press any time. - Do not use non-rechargeable batteries. If non-rechargeable batteries are fitted and start charging, it may cause the leakage of the battery electrolyte.
Please use only Panasonic P03P(Ni-MH) or P03H(Ni-Cd) batteries.