Battery going flat

Hi, My son has a 2003 1.1 petrol C3, the battery has been replaced. If the car is used every week for 30 minutes or so there is no problem, however, if it's left for more than a week the battery goes flat. Have tested for drain & it's almost nothing UNTIL, you open a door & then close it, there is then a continuous drain of about 1 amp, this only goes away of you remove the test meter, at that point it sounds like a relay clicks under the passenger dash. Closing the door does not remove the drain. Any suggestions please??? Thank you.

Hello captainpugwash.

I guess you replaced the battery to try and fix the problem?

How is it that you've noticed the problem, is it that the car has been used regularly in the past so the problem didn't show up or is this something that has just started to happen.

When you say that the battery drain is almost nothing, can you say what exactly it is?

You also say that after opening and closing the door the battery drain is about 1 amp. How long have you monitored this for? A battery won't sustain this amount of drain for a day never mind a week.

And finally, have you changed anything, eg installed a new radio?

I guess you replaced the battery to try and fix the problem?
YES, made no difference

How is it that you've noticed the problem, is it that the car has been used regularly in the past so the problem didn't show up or is this something that has just started to happen.
Since buying it 12 months ago!

When you say that the battery drain is almost nothing, can you say what exactly it is?
Well, with multimeter set to 10A it reads 0.12

You also say that after opening and closing the door the battery drain is about 1 amp. How long have you monitored this for? A battery won't sustain this amount of drain for a day never mind a week.
I was estimating! Multimeter set on 10A it reads 0.84 & seems to stay on that figure ( have left it connected for about 5 minutes), only goes back to 0.12 when multimeter is disconnected & the relay? clicks.

And finally, have you changed anything, eg installed a new radio?
No, but radio fitted is not the original one

Thanks for your help

The first thing I'd try is removing and disconnecting the radio, as the radio came with the car and so did the fault it's worth a try, aftermarket radios do seem to upset these cars.

Hi, Disconnected the radio but didn't make any difference, get same results.

captainpugwash wrote:Hi, Disconnected the radio but didn't make any difference, get same results.

You could try pulling fuses and using the results to work out which circuit is the problem and then fault it down to the service on that circuit?

Fuse box locations: https://citroenc3owners.com/citroen-c3-t ... s-t36.html

That sounds like a plan. If you have access to something like this you can speed up the process. This type of tester is available for different sizes of fuse, some do mini, sandard and maxi all in one tool.

Missing Lincs wrote: If you have access to something like this you can speed up the process.

Wow, that's cool. I have not seen one of these before. Looks like it can save a bit of time and not expensive either. Thanks!!
from maplin.co.uk

identifies the circuit draining your car battery• Suitable for maxi fuses • Provides an easy-to-read LCD display of the circuit's performance • Simply plugs into standard blade type fuse holder • Measures up to 48V/ 20A • Cable length: 400mm • Weight: 68g • Dimensions: 86(l) x 37(w) x 28.5(d)mm • 12V A23 type battery

I bought a cheaper one to start with but when I found out how useful it was I got a Sealey TA125, it has a higher current rating which means you can do virtually every car circuit except the starter. It also comes with adaptors to fit all sizes of blade fuse holder.

Here's the instructions for the TA125 clicky

One little tip with these meters, don't forget to put the fuse that you remove to do the measuring into the meter probe. I tested several circuits that had no current whatsoever before I figured that one