Relay draining both batteries...

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Dhammadad
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Relay draining both batteries...

Post by Dhammadad »

I wonder if you can clarify something. I had cause to go in my van earlier and both batteries are drained. Has to have something to do with the tracker I have fitted. I have had it 'immobilized' for a week and not taken it out but equally left it longer before without a run and he's started first time.

Would the permanent 12v feed into the relay be enough to drain it over a week? If so that seems to render the immobilizer a bit redundant doesn't it?
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bigbadbob76
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Re: Relay draining both batteries...

Post by bigbadbob76 »

Relay should only be on when the ignition is on, otherwise it would drain the battery quite quickly.
If that's how it's wired I'd look at changing it.
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CJH
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Re: Relay draining both batteries...

Post by CJH »

It depends what you mean by the 'permanent 12v feed'. The purpose of the relay is to join the +ve terminal of your main battery to the +ve terminal of the leisure battery. So of course those two wires will be live at the relay, permanently. But they should not be connected to each other until the engine is running, and until that time both of those 12v connections will be open circuit, so no, they won't drain the batteries. A fault in the relay could leave those two wires permanently connected to each other - a bit of dabbling with a multimeter should tell you. But even if the relay is faulty, and it leaves the batteries permanently connected to each other, that in itself will not drain them. There has to be something else drawing current.
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itchyfeet
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Re: Relay draining both batteries...

Post by itchyfeet »

if you have a tracker than can power a relay by txt commamd then surely its independent of ignition power?

I'd suggest they are not supposed to be immobilised for long periods by this relay, its something you can do it it gets stolen.

If you want long term imobilisation fit a manual switch
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Dhammadad
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Re: Relay draining both batteries...

Post by Dhammadad »

itchyfeet wrote:if you have a tracker than can power a relay by txt commamd then surely its independent of ignition power?

I'd suggest they are not supposed to be immobilised for long periods by this relay, its something you can do it it gets stolen.

If you want long term imobilisation fit a manual switch

Thats exactly what I have been thinking!

I am still curious (being a newbie) how and why a relay would suck so much life outta the battery??
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Ralf85
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Re: Relay draining both batteries...

Post by Ralf85 »

When you say drained, what was the voltage recorded on each one? Also, how old are the batteries?

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Re: Relay draining both batteries...

Post by 123-jn »

My Tracker uses about 8ma when idle. This peaks at about 60ma if I ask it to report position to me. In the summer I have a solar panel on the roof which replenishes both main and leisure battery but in the winter the alarm and the tracker will flatten the main battery too much in about 3 weeks. I now leave a trickle charger on when I'm not using it charging at up to 300Ma and cycling the batteries to keep them in good condition.
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Re: Relay draining both batteries...

Post by Dhammadad »

Thanks, I'm going to try leaving it 'off' for a week to see if that makes a difference. Why would a relay draw from the battery if it's not used?
VW T3 1988 1.9 78ps Devon 'Scotty'

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