Parasitic drain

Discussion in 'Mech Tech' started by Huyrob, Jul 19, 2021.

  1. Zed

    Zed Gradually getting grumpier

    Oh, it's intermittent. I guess your clamp meter might miss it too then?
    It's just advice, take it or leave it. :)
     
  2. Huyrob

    Huyrob Supporter

    I did say “if” Always happy to listen to advice. Hot isn’t it
     
  3. Zed

    Zed Gradually getting grumpier

    :oops: Yes it's hot, soz!
     
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  4. mikedjames

    mikedjames Supporter

    You know, car stereos, USB chargers, alarms, trackers...
     
  5. Zed

    Zed Gradually getting grumpier

    Er.. well I'll give you stereo, but mine keeps it's settings when disconnected and disconmected it is when ignition off. I thought this is loosing charge parked up so this and intermittant faults seems like grasping straws when IIRC nowt more than attaching a clamp and confirming a drain has occurred thus far?
     
  6. I used this method to find a shorted horn wire once!
     
  7. Zed

    Zed Gradually getting grumpier

    I worked back to the ignition switch once. It was powering things intermittently while switched off/keys out. Things like wipers (if I'd left the wiper switch on when I stopped the engine) would spookily come to life hours later was another clue but not the main drain.
     
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  8. Silver

    Silver Needs points/will pay!

    My aftermarket stereo used to drain the battery even when powered off. It came with the bus and I was never sure how it was wired, wether ignition live, permanent live or both. I tried removing the faceplate but wasn’t convince that this stopped the drain.
    With the faceplate on and switched off it used to come on randomly. I did think maybe it was a a Bluetooth remote version and it was picking up a signal from somewhere.

    I’d start looking at all the aftermarket items first.
     
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  9. Zed

    Zed Gradually getting grumpier

    Same here, I wired it's supplies via a switch so it couldn't mess me about and it still remembers it's settings.
     
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  10. Huyrob

    Huyrob Supporter

    Read your post a day or so ago, really good advice . Checked it over still a drain on engine battery about 25 ma. Gave up pulling fuses .etc etc. Still want to check Cunny 44 idea about Propex drain and still not tried isolating ( cutting off ) split relay charger.Thanks to Mike D James also.
    Totally fed up chasing shadows for now so fitted a cut off switch I took off my boat years ago. A bit of a faff but looks neat, works well and a reasonable anti- nick device. Just need to order a spare key ….and a big sign to go on dash to remind me it’s off
    Ps Snotty…you were right ⚡️⚡️
     

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  11. mikedjames

    mikedjames Supporter

    25mA is not enough to kill a starter battery in under 2000-4000 hours.. or 3 to 6 months.
    That is the kind of current a computer controlled widget will draw. Like a "hidden" tracker. Which will also tend to increase briefly to try to send data if you disturb the bus.
     
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  12. Zed

    Zed Gradually getting grumpier

    True, but personally I wasn't happy until I saw zero because I do sometimes not drive it for a month or more - it's always winter, the battery's cold when... be dammed it won't start! Then I have to put the battery in a wheelbarrow 200 yards to boat to recharge it by which time Tesco is shut anyway. :)
     
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  13. Huyrob

    Huyrob Supporter

    Whilst to start with I had no idea what currents etc would flatten, I am trying to understand. I appreciate that whilst I have swerved the issue I have not solved it.
    Reminds me of an occasion in my working life when a junior barrister gave a great explanatory speech to a pompous judge who reacted “ Thank you for that ..but alas I am non the wiser “ Junior counsel ( scouser ) replied … “ You may be non the wiser M’lud but you are certainly now better informed “
     
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  14. It’s something lurking that isn’t fused through the main fusebox. Worth tracking it down…
     
  15. Huyrob

    Huyrob Supporter

    Thanks Snotty, at risk of being a bore I had van MOTD a few days ago. failed on minor things 1. One headlight beam too low , 2.rear stop lights not working ( Jk switch only lasted 8 months ! ) **
    3. Rather odd …no windscreen washer working. It is an electric pump , thought water empty but no. Checked it ( had new loom fitted by a well known person on this site ) checked it out , strangely 12v was present with ignition off, but push button not activating. Took it apart and set up on bench .. all working , pump and switch. Rewired in van with new earth and working on ignition. All ok. Presumably it was the defective earth? Could this have been draining my engine battery…the feed was not fused and was live from engine battery .
    ** on question of brake light switch, bought new one from Schofields, double the cost of JK but interestingly Schofields website acknowledges previous problems with *** and have sourced a German company whose product is superior and “ to bear this in mind “ when comparing prices .
     
  16. Unlikely to be the pump/earth, but who knows? Supply for pump should really be taken from one of the fuses in the fusebox.
     
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  17. Zed

    Zed Gradually getting grumpier

    I'd agree, who knows? I never knew what my leak was, still don't but it's small and with the new ignition switch stopping it when the ignition is off I no longer care care. :)

    Have you not measured with your clamp meter?
     
  18. Huyrob

    Huyrob Supporter

    Hee hee
    Hee hee,
    Must be cooling down there by now ! useless bit of kit prefer to accept accept/ listen to advice
     
  19. Zed

    Zed Gradually getting grumpier

    I've been well behaved since that one post. :)
    Yes much cooler today thanks.

    When I was little and naughty, my mother would sometimes say Behave! to which I apparently would reply "I'm being have!"
     
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