current leak

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Mon 7 Jul 2003 10:45
current leak - Drew20
Does an 80 mA current drain sound a lot? This all goes through one fuse which powers the cigarette lighter, the clock, the interior light and the radio. I haven't traced the leak any further as it hasn't caused any problems yet.

I've done the maths and with my battery the drain will drain the battery totally in 2.5 weeks but I imagine it will make itself felt earlier than this.

is 80mA normal? or might it be a faulty clock?
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Mon 7 Jul 2003 12:24
current leak - Dynamic Dave
Lets see, a current drain of 80mA would work out to 0.96 watts of power being consumed. (0.080 amps x 12 volts)

Don't forget that the radio will also draw a small amount to keep the preset memories, etc.

Why not disconnect each assessory in turn that is connected directly to the battery and see what difference it makes to the current drain?

What size battery do you have? By my calculations, I make it just under 35 amps. That doesn't seem a very high capacity battery. Most cars these days would have a 45 amp one fitted as standard.
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Mon 7 Jul 2003 12:50
current leak - Drew20
thanks Dave,
37Ahrs for the battery (on the label.) Even with 45 Ahrs the battery would be dead in just three weeks and most likely in difficulty after two. I don't know whether or not this is normal, hence the post.
I will disconnect the clock tonight to see if the current falls any.
Might think about putting the radio on the accesory position on the key too
cheers
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Mon 7 Jul 2003 13:52
current leak - Altea Ego
If you take off the permanent feed for the radio thro the ignition you will have to put in the security code each time. Is there current drain for the alarm / imobilisor?
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Mon 7 Jul 2003 13:59
current leak - Dynamic Dave
=>> If you take off the permanent feed for the radio thro
the ignition you will have to put in the security code
each time....


And quite possibly re-enter the preset stations.
For reference, the current drain on my old Cavalier with the alarm set was somewhere ITRO 50mA.
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Mon 7 Jul 2003 14:45
current leak - Drew20
cheers, that sounds reasonable. My car has no alarm so I suspect that 80mA is due to a fault.

as to the radio, I assume mine must have a memory as I disconnected the battery last week and the radio remebered the time and its presets (no code as it is a face off unit).

isn't the radio on a ford always connected via the ignition? was on my fiesta
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Mon 7 Jul 2003 16:20
current leak - Altea Ego
The current (intentional pun) favourite way of powering radios is to have two power feeds. One switched by ignition, one unswitched ie always powered. The switched lead normally is just a "power up" signal.
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Mon 7 Jul 2003 21:25
current leak - none
Assuming that you have the various codes etc. needed to restore things back to as they were, the easiest way is to connect your ammeter and take each fuse out, noting when the current draw drops to zero. Check which circuits are covered by this fuse.
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Tue 8 Jul 2003 11:59
current leak - Drew20
yes thanks, done this and it all goes through fuse three
interior light (expect 0)
cigarette lighter (expect 0)
clock (expect v small)
radio (expect v small)

so will check clock
can check radio too

will report back when I have specific numbers for each component
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Mon 7 Jul 2003 21:40
current leak - smokie
I imagine presets must be maintained in a non-volatile memory, similar to your computer settings, as they aren't lost when the radio is removed. However computers have a small battery for the purpose.
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