Parasitic Draw Clio 182

[Jonesaaaay93]

Hello all,

I'm looking for some help and advice from anyone with a bigger brain than me (this should therefore be a very active thread!).

I have been having an issue now for quite some time with my Clio 182 draining batteries completely flat.
To give you the whole story;

Car was off the road for a few years, last summer we got it back on the road (after my daily car was stolen...). Part of that process included a brand new battery and alternator.
Fast forward 4 or 5 months and my boot solenoid started playing up and eventually stopped working all together. I don't drive daily (perks of working from home somewhat) so the boot not working wasn't a pressing concern for me to I left it for a while. A few weeks later I started to notice the car taking a couple of tries to start, then eventually battery has become completely flat and car will not start. We test the battery and its fine (no faults just flat) - we replace it anyway and only a couple of weeks later the same story unfolds - car goes from starting first time, to starting after a couple of turns, to completely dead battery. Same thing - battery is flat. It's worth noting at this point that we noticed that when the battery was flat (or I had disconnected the battery), the boot started working again which made us believe it could be the faulty solenoid draining the power. So, we give the battery a full charge, and at this point I believe we also changed the solenoid. All looked well this time, car was starting up fine, and we past the usual days/weeks without an issue. Then one day I came out and can you believe it, battery is dead again.

We believe the alternator is fine - first indicator is that the car will start and fire up no issues while the battery is charged - and on frequent occasion I have gone to the effort of disconnecting the battery overnight (even days at a time) and the battery is always charged when I come to plug it back in - so on the occasions I do take it out, it is all happy.
There is no aftermarket radio - although the radio currently doesn't work so I'm unsure if everything is plugged into the back of it...

Long story short - what are the best ways to test for some sort of parasitic draw/fault? Is there anything that I could easily do/check to identify the problem?

Appreciate it is likely a 'needle in a haystack' scenario, and all of the above may not be of any relevance so apologies if you read that and it's not!

 

[Louis]

Use a multimeter across each individual fuse, or straight onto the battery and remove fuses as you see fit.

You'll be able to then see which area it's coming from when it drops off.

 

[Jonesaaaay93]

Use a multimeter across each individual fuse, or straight onto the battery and remove fuses as you see fit.

You'll be able to then see which area it's coming from when it drops off.

Ahh amazing thank you so much! I will give it a go and see where we end up!

 

[Yarp]

Mine had that and it was the alternator. It’s happened twice. For some reason it decides rather than generating electricity it’ll try to be a motor and draw voltage. No idea how/why.

Test it by taking the big power wire off the alternator and see if it still does it.

 

[Jonesaaaay93]

Mine had that and it was the alternator. It’s happened twice. For some reason it decides rather than generating electricity it’ll try to be a motor and draw voltage. No idea how/why.

Test it by taking the big power wire off the alternator and see if it still does it.

Ahh ok thanks, we will have a double check on that too - we had the car running at one point and disconnected the battery and I was told that was proof that the alternator would be fine?
But I guess if it's a draw then that wouldn't be obvious from that test?

 

[Louis]

Ahh ok thanks, we will have a double check on that too - we had the car running at one point and disconnected the battery and I was told that was proof that the alternator would be fine?
But I guess if it's a draw then that wouldn't be obvious from that test?

You really shouldn't do that

 

[Jonesaaaay93]

You really shouldn't do that

Noted 😅

 

[Robbie Corbett]

Yea don't do that!

If the alternator has a fault the battery is the only thing keeping output voltage in check. A faulty alternator is capable of well over 40V which would damage every module on your car.

Plus an alternator can fail but still hobble on enough to charge a battery - its a s**t test.

My alternator failed as a dead short across the battery and nearly caught fire. Your best bet is to do as Louis has said, with an additional test which is to disconnect the positive cable from the alternator and bridge it with your mustimeter set to amps to see how much current the alternator is drawing with the engine off.

If its basically nothing, then move onto pulling each fuse one by one and again connecting each probe of your mulimeter between the fuse terminals with the meter set to amps. Make a note of the current for each fuse location.

 

[jenic]

Mine had that and it was the alternator. It’s happened twice. For some reason it decides rather than generating electricity it’ll try to be a motor and draw voltage. No idea how/why.

Test it by taking the big power wire off the alternator and see if it still does it.

I had this too, iirc there are two positive feeds on the 182 battery, one goes to the engine (alternator and starter) and one to everything else, so testing accross these will help identify if it's engine side pretty quickly,

 

[Robbie Corbett]

I had this too, iirc there are two positive feeds on the 182 battery, one goes to the engine (alternator and starter) and one to everything else, so testing accross these will help identify if it's engine side pretty quickly,

Pretty sure they are all crimped together so can't be disconnected individually at the battery. I believe he will need to disconnect at the alternator.

 

[Jonesaaaay93]

Thanks for the input guys! (I did stipulate my lack of brain cells in the original post 😅 )