Dead battery again !

Couple of months ago the battery was dead after leaving the p38 for a week, i left it on charge untill fully charged and it's been fine since, last weekend i drove a 340 mile trip and all was well.
Yesterday, the battery is dead again?, the dash has been showing a alternator fault ever since i brought it last september, do you think the alternator is knackered ?.

richp1970 said:

Couple of months ago the battery was dead after leaving the p38 for a week, i left it on charge untill fully charged and it's been fine since, last weekend i drove a 340 mile trip and all was well.
Yesterday, the battery is dead again?, the dash has been showing a alternator fault ever since i brought it last september, do you think the alternator is knackered ?.

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I wouldn't have thought so!!:doh:

did you clean up the connections and re check battery terminals

Could easily be a dodgy diode pack in the alternator allowing the battery to drain back through the alternator windings.

You can get a new alternator from Paddocks etc. for just over a ton.
Couple of years ago when I was putting a new engine in my 4.6, decided to get the alternator and starter checked out at a reputable company who fitted new brushes in both. The starter was fine but the alternator, after the engine was started, was pulsing up to 17Volts causing the lights to brighten at around 3 second cycle. Rather than risk possible damage to the ECU's, I sent for a new unit which was Delco Remy and has been working perfectly. With known problems,alarm related, on the P38, a fully charged battery is essential-otherwise you will be beset with problems