Leaking clock batteries
Many Amigas have a small rechargeable battery for the clock. Over the years it leaks an alkaline liquid that corrodes the traces on the board. It is the most common avoidable fault of all.
Difficulty: Take careTime: 1 h
⚠ Before you start
- Wear gloves: battery liquid is alkaline and irritates the skin and eyes.
- Always work with the machine unplugged from the mains and from the power supply.
Where they are
The battery is usually a small blue, green or black cylinder soldered directly to the board. It is found on the Amiga 500's A501 expansion, on the main board of the A500 Plus, A2000, A3000 and A4000, and on the A600's A604 expansion.
The signs of trouble are greenish, white or bluish crystals around the battery, traces that have changed colour, and nearby components with darkened legs.
Removing and cleaning
The rule is simple: even if the battery still looks fine, remove it. The clock is not needed for the machine to work.
- 10Remove the board (or the expansion) from the machine.
- 20Remove the battery by desoldering it. If you don't have a soldering iron, cut the legs as close to the battery as possible and leave the rest to remove later.
- 30Neutralise the residue: with a soft brush dipped in white vinegar, gently scrub the affected area. Vinegar is acidic and neutralises the alkaline liquid.
- 40Clean off the vinegar with isopropyl alcohol and let it dry thoroughly, for at least a few hours.
- 50Inspect it with a torch and, if you have one, a magnifying glass: the traces should be copper-coloured or the green of the solder mask, with no dark stains. Traces that have been eaten right through need to be rebuilt with wire.
If you still want the clock
There are holders for lithium coin cells, mounted away from the board or on a small separate board, and modern rechargeable batteries. What matters is that, if it ever leaks, it doesn't leak on top of the chips.
When to bring it to us
If the corrosion has reached fine traces, vias between layers or chip legs, the repair needs continuity measurements and connections rebuilt. That is exactly the kind of work we do on the bench.
Request a repairThese guides are for information. Working on old electronics carries risks: do it at your own risk, with the machine unplugged, and never open power supplies or CRT monitors. If in doubt, bring the machine to us.