Battery Failure?

[Error404]

Odd things going on yesterday! Not driven the coupe for a few days, its been parked up on the drive. Got home from work yesterday (I walk) and noticed an odd scratching / sqeaking sound coming from the engine bay. I grabbed the keys to have a look, but the remote locking not working, so opened the door on the key and turned on the ignition, volt meter didn't even flicker. Battery is flat. In the engine compartment the scratching/sqeaking sound is coming from the Toad siren. I unplugged it and the disconnect siren bleeped a few times really quietly then stopped.
So I grabbing my Ctek and plugged it in, I figured I'll charge the battery up and then test to see what has discharged it.

As I turned the charger on all kinds of weird **** kicked off! Pretty much every system on the car started pulsing, the interior lights were pulsing on and off, loads of relays were clicking under the dash, indicators were pulsing, dash lights, climate headunit, our old mate the Toad siren started doing its scratching, squeaking routine and the after-run pump was pulsing! WTF, my car is possessed!
The volt meter still not registering anything at all. Took the negative terminal off the battery and it continued so the charger pulses were kind of going straight through the battery. Never seen anything like that before, so I'm really none the wiser, I wondered if the battery itself might have a damaged cell internally? It won't take any charge anyway. It was the first thing I bought for the coupe when I bought it almost 8 years ago, so its done pretty well - Varta Black series. Previous to this I had never had any issues starting the car and I could leave it parked up for 2 weeks and come back and it would start first time, up until I last drove it which was Tuesday evening.

I've ordered a new Varta Silver 096 anyway, will get that fitted and see what happens.

[4WheelDrifter]

Have you tried to charge the battery disconnected, using a multimeter to check what's going on with it? That sounds odd.

[K Simmonds]

Sounds like a duff battery to me and the pulses from the charger probably explain the weirdness combined with the alarm system which is likely quite sensitive to voltage variations.

Eight years isn't too bad a life for a battery at all, anything over four or five years is a bonus, though I have a Halfords one that came with car from Tristan and that's at least 10 years old and still going strong.

[Error404]

Have you tried to charge the battery disconnected, using a multimeter to check what's going on with it? That sounds odd.

Yeah I disconnected the car from the battery, and left it an hour, didn't even nudge the volt meter when I plugged it back in.

I have to say the Ctek does seem to keep the battery in great condition. I have abused this one a few times and its come back from the dead. Not this time though

[GazzaG60]

my old bosch went like that the other week. i had a silver wouldn't tske any charge. having said that it was like 10 yrs old and not run a car for a couple o years. got a exide from ecp last week.

does then job so far

[Monkeymagic]

I found those ctek battery float chargers won't touch a completely flat battery. It certainly sounds like the battery is dead.

[Vorsprung durch Technik]

Definitely sounds like the battery is gone.8 years is a good innings anyway. Bolt new one up and she will be fine!

[mcandmar]

If the battery voltage is low enough those little chargers wont start. You really need an old fashioned brute force charger to kick the battery back into life, or jump start the car to get the voltage upto a level where the ctek will start.

[mike74]

My mate's old pug 205 had something similar happen when he was driving it. ALL the electrics in the car jumped into life at once, even though they weren't actually switched on; turned out the voltage regulator had died. By the sound of things, I would suggest the flat battery is a symptom rather than the cause. We've all had flat batteries I'm sure but I've never heard of something like this occur. It almost sounds like a positive wire has been connected to the negative somewhere. Can you shove the old battery back in and try jumping it from another vehicle to see if the same thing happens again?

[Fat Audi 80]

Your battery is ****ed. My alarm used to play merry hell when the battery went flat. A new one should cure it.

[220bhp]

Had this on my s2 Alex. I disconnected the alarm siren some time ago so didn't no alarm was going of. The bonnet stops where not adjusted right and stopped the bonnet closing on drivers side enough to deactivate the alarm.
Every day the battery was flat. I tried to charge it but no luck. As said above modern chargers wont work if there's not enough power in the battery.
Bought a new battery, and in a couple of days the battery was flat. That's when I discovered the fault with the alarm My milkman said, how come your lights are always flashing. I now have less money, and a spare battery.

[macspring]

Thanks for sharing, wouldn't have thought of this one straight away.

[AndyP]

Did you get a new battery?

[Error404]

Yes I did
Seems I have an issue with the after run pump system randomly coming on, this seems to have been the culprit. Not had time yet to investigate why so just unplugged it.