how long will a battery hold its charge

[wooly12345]

2 weeks is the longest i've tried it, started fine

[bl52krz]

If you are not arming the alarm or locking the doors,then either there is a fault with the battery, or it is being drained by something else. Have you checked the alternator is not draining it. Sometimes you can take the belt off the alternator and you will find that the alternator shaft will be turning round slowly.

[murphyv310]

Hi.
Its not just Rover that has the problem. On a modern car not only does the alarm use power but the body computer and other items like radio backup, clock, navigation and srs are powered constantly. OK so the current used is small but that along with natural discharge of the battery and humidity effects all can add up to a flat battery a few weeks down the line.

[kentish]

I would be concerned if you are leaving the alarm off and it will not start after 3 weeks. My ZT is used approx once every 2/3 weeks with the alarm on and it starts first time. The battery on this car is about a year and a half old. Given the weather hasn't been that cold I would rather suspect something is amiss.

[alanjay]

Originally Posted by murphyv310

Hi.
Its not just Rover that has the problem. On a modern car not only does the alarm use power but the body computer and other items like radio backup, clock, navigation and srs are powered constantly. OK so the current used is small but that along with natural discharge of the battery and humidity effects all can add up to a flat battery a few weeks down the line.

Thanks for that, I only considered the alarm and clock, perhaps disconnecting the battery is the answer but of course that could lead to other problems.

[marinabrian]

I left Frosty for five months, and he started first click

Diesel parasitic battery drain problems, are normally due to a defective glow plug relay.

You can disconnect this and see what happens, or remove fuselink six in the engine compartment fusebox, this is the furthest right of the large links in the centre of the fusebox, screwed into the +VE busbar

Hope this helps

Brian

[Westonboy]

Originally Posted by bl52krz

If you are not arming the alarm or locking the doors,then either there is a fault with the battery, or it is being drained by something else. Have you checked the alternator is not draining it. Sometimes you can take the belt off the alternator and you will find that the alternator shaft will be turning round slowly.

Thank you for your advice, I have little knowledge about car electrics, If I don't alarm the car and it has a flat battery after a couple of weeks of being garaged I obviously need to get it checked out by a competent auto electrician.

[crashmarks]

Originally Posted by Westonboy

Thanks for the opinions,All I would like to know is ,should my 75 be able to go for more than 3 weeks garaged without a flat battery or should I be concerned and get an auto electrician to check it out

Yes you should get it checked out the car should be able to stand a lot longer than three weeks without a flat battery assuming that the battery fitted is in serviceable condition. In the unlikely event that your new battery is faulty then something that shouldn't be is drawing current and you need your sparky to get to the bottom of that.

[Westonboy]

Off to bed now, Thank you for all those members that have offered advice.

[Forestgreen]

I left my 2.5 V6 in an airport carpark for three weeks one chilly November and returned to find it started fine.

The foollowing winter I left it for a week during a particularly cold snap as I didn't want to drive it in ice and snow, and it wouldn't start. To be fair it had been struggling to start for a few weeks prior to this, so I replaced the battery and it has been fine ever since.