Gardena C1060 Plus Solar 7.4V Li-ion Replacement Battery

My Gardena water computer stopped running its scheduled cycles overnight — is the solar battery just dead or is something else wrong?

If the unit stops executing schedules but still powers on, the battery has likely dropped below the threshold needed to drive the solenoid valve, even though the display still has enough juice to light up. A degraded 7.4V lithium-ion cell can read 7.0V at rest but collapse under the brief current spike the valve demands. Pull the battery and check its resting voltage with a multimeter — anything below 6.8V means it's no longer holding a usable charge. If voltage looks fine, check that the solar panel face isn't shaded or filmed with dirt, since a partially charged cell compounds the same problem.

I replaced the battery but my C1060 Plus Solar is losing its programmed schedule — keeps resetting to defaults after a day or two.

This is a low-voltage event during the panel-to-battery handoff, not a programming error. When the replacement cell is too deeply discharged on arrival and the solar input is marginal, the controller drops power briefly and wipes volatile memory before the battery can stabilize. Charge the new battery to full via a compatible external source before installing it, so the solar panel is topping up rather than recovering a flat cell. After installation, leave the unit in direct sun for a full day before programming, then confirm the schedule holds overnight.

The solar panel is getting sun but the new battery doesn't seem to be charging — water timer keeps going flat.

At 800mAh and 7.4V, this cell needs the solar input to be clean and unobstructed to recover meaningful charge across a day. The most common cause after a battery swap is a poor contact seating — the cell's terminals not making full contact with the spring pins inside the compartment, which drops the charge path to near zero. Remove the battery, check for corrosion or debris on both the battery terminals and the device contacts, and reseat firmly. Then set the unit face-up in unobstructed sun and measure battery voltage after four hours — it should have risen by at least 0.2–0.3V if the charge path is intact.