Flooeded rear light corner unit, dead battery

[PeteTheGreek]

So my re-sealing up of the rear light cluster from 12 months ago has failed, and flooded the light unit again with about 2 inches of water corroding the bulb holder, and the 4 pin connector.

I've taken it apart, dried it out, and ordered new bulb holder, connector and indicator bulb.

My question is though, before I noticed the light was flooded, my battery was flat when I wanted to use the car 2 weeks ago, charged it up, then the car would only just about start after it's 7 hour charge. It was then flat again a week later, recharged it, and the same thing happened.

Is/was the corroded light connector/holder shorting the battery out and flattening it? I can't remember if it did or not from the last time the light flooded. I've got it on charge again with the light unit removed so will see what the battery looks like later.

 

[paddy]

Depends on your charger, if its a small 2-3 amp/hour unit, 7 hours would put about 20 amps in the battery which is probably an 80 amp battery so barely 25% charged

 

[45bvtc]

I have a spare battery - just taken from my 8P RS3 - if you need - collection only...
VARTA/AUDI 5K0 915 05H - 12V 80Ah 380A DIN - BEM Code: 5K091505H

Just swapped both (same) from my RS3 and TT:

 

[PeteTheGreek]

Cheers, looks like it's a dead battery, i'm using a trickle charger it said it full charge last night after charging, but only had 13.3v, checked it this morning it's on 10.5v. Going to test if there's a drain on it somewhere before getting it to the garage.