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MG MGF Technical - flat battery

my 98 mgf battery goes flat after 3 days of no use done all the basic tests brand new 500 amp platinum battery disconnected earth and measured with new multimeter between battery and strap measuring 0.04 milliamps dont know what to do know had battery tested cleaned earths and fitted new ones to engine and battery cleaned starter connections have i missed something
rj hardwick

Was the car locked with the alarm armed when you carried out the drain test?
Sam Murray

If the problem is the infamous sticking-on-ECU power-relay, then disconnecting the battery is probably enough to clear it. When you reconnect the ground through the multimeter to measure the current drain you would then probably only see the correct alarm drain current of 30ish milliamps.
A cheap and cheerful 1st aid might be removal and hefty use of electrical contact cleaner on the ECU connectors and its relay. I am also assuming you are disconnecting the new battery from the car when returning it to fully charged?
Otherwise the alternator may be worth investigation - discharging the battery when left connected after normal running. Particularly if previously externally heavy charging the battery whilst still in circuit. Good luck.
Charless

already stripped relays and sprayed but they were in perfect condition checked alternator pushing out 14.5 v donno what else to do
rj hardwick

I have a similar problem on mine, apparently the alarm is often the culprit and there are other threads on it. All in all I decided to put her in to an auto electrician for testing but have not done it yet ;)
Russ68

This thread was discussed between 19/02/2011 and 18/04/2011

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