Discofan Posted May 25, 2010 Share Posted May 25, 2010 I have a 300tdi. When used every day there is no problem but if it left for a week and a half or two weeks without running, the battery although it has power, hasn't enought to start the engine. Jump leads immediately start it , no problem, Any ideas?? Cheers Quote Link to comment Share on other sites More sharing options...
pinhead Posted May 25, 2010 Share Posted May 25, 2010 sounds like you have iether got a drain or the battery is shot get battery tested first thats easyest Quote Link to comment Share on other sites More sharing options...
Les Brock Posted May 25, 2010 Share Posted May 25, 2010 Alarm ? Radio memory ? Quote Link to comment Share on other sites More sharing options...
BogMonster Posted May 25, 2010 Share Posted May 25, 2010 Battery drain would be my guess, check the discharge with everything off. If it's a few tens of milliamps that is normal, if it's a lot more then you have a problem. Doesn't sound like a lot but 0.5 amps x 24 hours = 12 Ah x 7 days = a completely flat 80Ah+ battery. Quote Link to comment Share on other sites More sharing options...
ChrisB Posted May 25, 2010 Share Posted May 25, 2010 A few simple checks (assuming you have a volt/multimeter!): What is the battery voltage before starting after being off overnight? What is the battery voltage immediately after starting (within 30s)? Immediately after starting, what is the voltage with positive lead on alternator casing, and negative lead on negative battery terminal? Post up some voltages and we can help further :-) Chris Quote Link to comment Share on other sites More sharing options...
Richard Mills Posted May 25, 2010 Share Posted May 25, 2010 A few simple checks (assuming you have a volt/multimeter!): What is the battery voltage before starting after being off overnight? What is the battery voltage immediately after starting (within 30s)? Immediately after starting, what is the voltage with positive lead on alternator casing, and negative lead on negative battery terminal? Post up some voltages and we can help further :-) Chris Quote Link to comment Share on other sites More sharing options...
Richard Mills Posted May 25, 2010 Share Posted May 25, 2010 Hi There, Mine was doing the same, and I did all the checks, but it was in the colder weather. A new battery fixed it, though the old battery is still good enough to jump start other cars with. I did however create a problem, jump starting it every day made the srs lights come on, and they are still on today. Take care. Quote Link to comment Share on other sites More sharing options...
Niamh Posted May 25, 2010 Share Posted May 25, 2010 I think it's low voltage that causes the SRS light problem, the fault condition needs clearing from the control unit. Niamh Quote Link to comment Share on other sites More sharing options...
TwelvestringTrev Posted May 31, 2010 Share Posted May 31, 2010 Sounds like one or more of the 6 battery cells are shot. Each cell gives off 2 Volts. 10 volts may start the engine but any less than that wont. Battery posts becoming hot under load is a common sign and bubbling of the battery after attempting to start the engine. You could do no harm by topping the battery up with distilled water. It may be just low. Good luck ! Quote Link to comment Share on other sites More sharing options...
Andy Posted June 2, 2010 Share Posted June 2, 2010 As a quick test disconnect the battery when you park it up. If it still won't start a week later the battery is goosed. If it starts then something is draining it. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.