Renault Scenic 54 battery draining overnight
I go out in the morning and the battery is flat and all is dead. I charge the battery, the car works for a few days and then it happens again. It has had new battery and the mechanic cannot find anything wrong with it or the car. The first indication of the intermittent fault that I can see is that the touch unlocking of the back door does not work - does that mean it is the central locking that is causing the problem or is that the first to go as the battery gets low? "Check Emissions" sign is also always on. Also, RAC man who came out to me once said I should disconnect the battery before charging. Anyone know how to do that? I fear that this intermittent fault is going to prove very expensive.
I assume the mechanic that looked at your car checked the alternator was functioning and the auxilliary belt was tensioned correctly and he/she checked for a current drain?
It is impossible for a good battery to discharge overnight without a detectable current drain on the battery.
Most likely culprits are the boot (or another interior) light staying on and draining the battery or a bad earth connection somewhere but it could also be a number of other things inc a faulty door lock.
To disconnect the battery you need to disconnect the negative lead on the battery whilst charging but to be honest with modern chargers and batteries, if you are trickle charging overnight this isn't really necessary and would mean you would have to reset the clock, radio code etc.
As for the "check emissions" lamp, this really needs to be put on a scan tool or fault code reader for further investigation.
Hope this helps.
The two things that strike me are firstly the reference to 'the mechanic' as opposed to garage, the second is that if there is a fault with your car battery draining, this should be a relatively simple matter for a mechanic to resolve. It is a matter of checking the battery condition, charging system and checking for a drain. Battery is either OK or not, charging system is OK or not, and drain, although it could be intermittent, shouldn't be too hard to find by a process of elimination.
Contrary to post above, I would always recommend battery disconnection before charging from a mains battery charger, as I have seen too many problems occur after charging without disconnection.
Renault Scenic 54 battery draining overnight
Thanks for the response. I have now just got my car back from the Renault garage (Friday, having left it there on Monday morning) and they could find nothing wrong as the wretch started perfectly every morning. Nothing came up on any of the computer tests and the alternator is fine. The only thing - unconnected with battery draining - is that they said the camshaft sensor will have to be changed as it is that that is causing the "check emissions" message to come up. As it is an intermittent fault I don't see how they could have found it anyway as they would only have tried to start it in the morning and it would have been dead and what would that have revealed? Any more suggestions would be gratefully received as I don't know where to go next.
Update on Sunday - battery dead in the morning both yesterday and today.
Last edited by childes344; 10-08-08 at 10:46.
Reason: Battery then dead on two following mornings
I think I'd take it to a specialist auto electrical garage for a check over. They will have more incentive than the dealer for trying to find the fault. Find a well known garage that specialises in this work such as LS (UK), a national network that gaurantees its work.
Scenic battery draining
Thanks for the advice. I had the RAC out again this afternoon to start it and he suggested the same. He also wondered if the new battery I had put in when this problem first started was faulty. I wil get that checked tomorrow and contact the electrics engineer he recommended.
Hi I have the same problem please let me know if you find the problem and i will do likewise
The battery drain over night could be the passenger glove box, they are almost all out of alignment and don't switch off the light when you close the box lid. Try sticking a plastic pad over the switch to give it more chance of switching off.
The auto door locks are prone to stop and start working when they can be bothered. I had six replaced under warranty and now it is out of warranty I haven't bothered as they cost £700 to replace each time. I find during the summer (If dry) they work fine, cold or wet they stop working, same happens to the electric folding mirrors.
Typical French quality I'm afraid, they pack in all the extras but don't make any of them last more than three years.
The electric engineer can't find the problem having had it for three weeks (but the chap in charge was away for two of those and he has had people away this week). It was dead the first morning but hasn't happened since although they say they have had it out during the day. Does anyone know if the battery completely gets flat the computer resets but if some power still in it the fault will still be recorded? I am going to collect it tomorrow so don't know what to do next. We will certainly try the glove box light pad, though.
Since collecting the car nearly two months ago it has started perfectly every day (although I am touching wood as I write). The engineer said that he checked everything and if it was a loose connection somewhere that might have fixed it. He also took out the boot bulb, the glove box bulb and the bulb inside the centre console between the front seats. I have not tried to replace any of them yet as I am leaving well alone. Fingers crossed!
Last edited by childes344; 27-10-08 at 21:52.
Reason: Update nearly two months after last post.
I'd try disconnecting the main lead at the alternator. If there is a short in it, it can drain the battery. Worth a try.