Flat battery!

Discussion in 'Mechanical - Engine, Gearbox, Exhaust etc' started by Alex_225, Apr 16, 2014.

  1. Bit of a strange one, my battery died completely in my 225 Trophy at the weekend. Now I put it down to the fact that I'd left the OBDII Bluetooth dongle plugged in and the constant LED had drained the battery.

    So put the car on a fast charge, removed the dongle and let the battery charge up and showed full on the charger. Car started perfectly and did a fair old drive on Sunday without issue.

    Came to start the car last night and battery dead again, to the point where it struggled to lock the doors after I'd tried to start her.

    I'm trying to find out how old the battery is in the car as I'm pretty sure the previous owner said it wasn't that old but before I go out and buy a new battery, are there any other likely causes for it to drain?

    My suspicion is that the previous owner only drove it infrequently, I only drive it about 100 miles a week anyway so I'm wondering if the battery has been dying in it's ar$e for a little while but any advice would always be handy. :smile:
     
  2. Get it running and take it to local motor factors, they can test the alternator for charge and also drop test the battery to see if it's goosed. Battery's are prone to failing through winter so that may well be your problem.

    hope this helps
     
  3. A word of warning too don't bump start your car to kick the battery into life, the sudden demand on the alternator to power up the flat battery can fry it.........words of experience.
     
  4. Thanks for the info there mate, much appreciated.

    By bump start, do you mean rolling it and trying to get it started in say 2nd gear? I've jump started my other Megane many a time without problem but used a mains powered charger/jump starter to get it fired up not bump starting. :smile:
     
  5. Yes exactly that, I've done it many times myself but did it on a polo last week and it blew the alternator, happened to my pals s3 too
     
  6. Oh b*gger, well I definitely won't be doing that. I'll stick with jump starting off my battery charger :smile:

    I contacted the previous owner and it turns out that it's actually still got it's original battery so that'll be 9 years old so I think maybe my ODBII dongle has run it flat and it's failing to hold it's charge now. New battery on the cards me thinks. Can get a Bosch S4 from Eurocarparts for about £80 which seems to be a decent battery, better spec than standard anyway.
     
  7. Ash87

    Ash87 RSM Moderator

    My battery died with no prior warning the other week think that was the original, got new one on there and all was well.
     
  8. Should be fine yeah.
     
  9. What is it with batteries dying, mine went last week too with no warning. It was original battery so over due a change lol. After starting it with jump leads my electrics did go funny for a short period until the system had reset itself. Various error messages etc....
     
  10. Yeah the 225s always have a funny turn when they're completely out of electric.

    My other 225 has been disconnected various times from the battery, usually when stored over winter. Usually have to reset the windows, drive a short distance for ESC to reset and all that jazz.

    Went and collected that battery on Friday, fitted in the car (blue matches my Samco hoses haha) and car started perfectly. The old battery was definitely knackered as even after another charge it struggled.

    Only annoying thing is that now my drivers side window won't open. Suspect it's the window regulator but it's done this before and then started working again so we'll see how that behaves next time I use the car!! :smile:
     
  11. Will.

    Will. RSM Moderator RSM Moderator

    Are you sure the Bluetooth OBDII dongle has its LED on when the car and ignition is off? Mine has been plugged in for months and it's been fine.
     
  12. Yeah LED was on the entire time, ignition on or otherwise so I'm guessing with it being an original battery combined with a constant, all be it small drain it was enough to do it in.

    Also bear in mind that I only drive the car twice mid week (about 12 miles in total) and then a bit at the weekend so I suspect I wasn't putting enough charge back in to compensate it along with the old battery.
     
  13. MicKPM

    MicKPM RSM Trader RSM Trader

    As @will. mentions above a single LED flashing away won't draw enough current to kill a battery overnight which is why the vehicles security LED doesn't do the same nor will it keep the CAN active as everything else will be sleeping (no active +AI live which times out after so many minutes). If your battery is draining over night then some simple checks need to be done first on the battery and alternator to make sure they're both doing what they should and if they're okay turn your attention toward the UPC as it's most likely water logged.

    Mick
     
  14. Although, having stored my other 225 for fairly long periods of time there is enough drain to flatten a battery within a couple of months if the car isn't started.

    Considering that my Trophy was used infrequently prior to me buying it, combined with it having a 9 year old battery and now me driving it infrequently as well, I'm suspecting the battery was never getting properly charged back up. I'm not saying the OBDII dongle was the main problem but my logic suggests that if the battery is on it's last legs, any additional drain on the battery won't help. Also if the battery wasn't holding charge for more than a day or two my thinking is that the cells of the battery are knackered.

    Since fitting the new battery I've not had any problems at all and that was on Friday. :smile:
     
  15. MicKPM

    MicKPM RSM Trader RSM Trader

    My post wasn't aimed specifically at you btw Alex (sorry) - it was intended more as a "general info" if someone dug this post up at a later date.

    Your issue did sound like the battery itself would fail a load/drop test though
     
  16. That's ok mate, always good to get advice either way. :smile:

    I would have been surprised if the LED on that dongle was enough to drain the battery, well a healthy battery at least.

    I should learn to use my cars more I think haha.
     
  17. Will.

    Will. RSM Moderator RSM Moderator

    Yes. Stop neglecting it!
     
  18. Haha well I will admit to neglecting the inferno Megane. It's actually not seen daylight in the last two years!!! Mainly because of various things going on at home, busy with the house etc. That said it is currently detailed, covered, battery removed, dry stored on a foam floor in my garage so has been stored carefully. :smile:

    Must admit I am rather liking having a 225 as a daily car, much prefer it to the 172 although that was superb fun.
     
  19. Fitted exactly this battery when mine died think mine was the original battery too. Once it was left to go totally flat that killed it.
     
  20. Have you found the battery lasting well?

    As for the original, I think when an older battery ends up flat it fails to recover again. Oh well hope this one lasts 9 years like the last haha
     
  21. Had it for a year now and no issues
     
  22. Nice one, thanks mate. :smile:
     
  23. I have an R26 with Lux pack i.e. Keyless entry. What happens if the battery goes flat with the doors locked? Is there a manual override to open the doors? Cheers, Jon
     
  24. On the left side dor there is a small cower that you take off and you can unlock the car
     
  25. Thanks very much Milos I will check that out.
     

  • Share This Page