Amp battery drain

Hi all,

After not driving for a few days, I've just come back to a flat battery. This never used to happen before installing a stereo amplifier, although of course it could be a coincidence. The amp spends most of its life in a standby mode, as there is a cable from the head unit which switches it on when the HU is switched on.

Is it normal for an amp to drain a battery, even when it's switched off? I am willing to believe that the battery wasn't in the best nick, but still... What sort of current should the amp be drawing in standby mode? I wonder if the amp is faulty.

Antony

Reply to
Antony Gelberg
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The amp is most likely the problem. Personally, I'd wire it via an ignition controlled relay, so that it's completely turned off when the ignition is off.

It would probably be best to check the current drain. With everythingg of/in standby, battery drain should be neglible (less than 20-30mA). Anythin above that will be capable of draining the battery in a few days.

Reply to
Moray Cuthill

[snip]

It's got a remote wire, so it should do pretty much that as standard.

Possible things I can think of in no particular order:

  1. Head unit isn't switching off the amp (check voltage on remote wire).
  2. Amp isn't switching off (check current draw on vs off).
  3. Something else is doing it (switch everything off, check current drawn from battery, pull fuses until it goes away).
Reply to
David Taylor

The OP said it spends most of its life in standby mode, which is not off.

Dave

Reply to
gort

Yep. It's in standby. It powers a relay so it can turn itself on.

Reply to
David Taylor

An amp will drain a battery in a couple of days... You need to measure the actual current drawn by it - to find out if it's the culprit.

Reply to
Ian Stirling

Or, just disconnect it to see if there is any more (excessive) leak.

Reply to
Lin Chung

Measure the current at the battery.

Reply to
CWatters

Hi Antony,

I have a simple do-it-yourself procedure for tracking down excessive parasitic load problems in Section 10 of the Car and Deep Cycle Battery FAQ on

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You might be surprised what can cause the problem.

Kindest regards,

BiLL......

Reply to
Bill Darden

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