Technical Punto mk2 Battery Drain Problem

[MattMars]

Hi,

I have a 2002 Fiat Punto 1.2 Active Sport that drains the battery every 10-14 days. And I was wondering whether anyone could help me out.

I have a 6 month old battery which has been tested as well as a brand new alternator. I have tested both of these and found them to be working.

I have disconnected my aftermarket cd player and the problem still persists. I have left the CD player disconnected.

I disconnected the positive on the battery and tested the amps and found the battery drain to be 190 milliamps / 0.19 amps (far higher than the recommended 0.03 - 0.06).

I started taking fuses out of the fuse box by the steering column and the only fuse that had an effect was F53. When I took this fuse out the drain dropped from 190 milliamps to 60 milliamps.

According to the Haynes Manual Fuse F53 is "Hazard warning lights, direction indicators, instrument cluster".

Now that I have narrowed it down to this I was wondering if anyone knew what I could do to fix this problem.

Thanks very much.

 

[Ziggy122]

So its saying The indicators and dasboard are sucking power

I know this would sound outta the blue - but wonder if the hazard switch unit has failed?

Ziggy

 

[MattMars]

Thanks Ziggy, I will investigate that. The hazards work and all the lights flash properly. I will get the centre console off later and see if disconnecting the hazard button changes the drain at all.

 

[gvmllr]

could be a bad earth..or dodgy alternator not charging the battery.

 

[Ziggy122]

could be a bad earth..or dodgy alternator not charging the battery.

We've already diagnosed a heavy drain on the battery

it'd take 10 hours to drain 1amp
So times that about 2.5 amps a day
So 10 days at 2.5amps = 25amps

The battery is discharged at that point if its not recharged

So yes if you happy to remove the switch unit - then see what drain you have

Ziggy

 

[AndyRKett]

With the car door open the dash lights up to display the mileage. I would imagine it is something to do with this as to why you see 190mA there is a time out period on this so it might not be a truly accurate reading if you are in and out of the car swapping fuses about etc

sorry Ziggy but you can't calculate battery drain in the way you've done as first off how did you work out at 190mA it would take 10 hours to = 1A ?

standard punto battery is about 40Ah and about 0.48kWh (based on a 12V output)

0.190A over 10 days (240 hours) is about 0.45kWh (if my calculations are correct which they might not be) in anycase given your description of events i actually don't think there is any fault with the car its just the nature of Punto they don't like being left for more than week or the battery goes dead, if its going to be a problem to keep disconnecting the battery between uses then consider fitting a battery isolator switch ?

 

[Ziggy122]

**** my maths is out!

190 an hour = 5 hours todo 1 amp

That is still way to high - my punto could be left 2 weeks without draining the battery, never has

the drain is still way to high - the fault needs to be found - undoing and redoing the battery clamp or fitting a switch is just a ball ache

Ziggy

 

[MattMars]

Ziggy,

I got the centre console off and detached the two cables that go to the panel with the hazard light switch. When I disconnected the hazard light switch the drain stayed the same at 190 milliamps.

I think my next move will be to disconnect the instrument panel on the dash and see if the changes anything. I will keep you posted.

 

[MattMars]

SOLVED!: For some reason.

I disconnected the instrument panel on the dash and the drain went from 190 milliamps to 40 milliamps so I was thinking that I will have to get a new instrument panel.

I reconnected the instrument panel and put it back and the drain stayed at 40 milliamps! I have no idea why, but since I disconnected and reconnected the instrument panel the problem has gone! All I can think of is that maybe one of the connections to the panel was dodgy and reconnecting it fixed it, I don't know. The car has been starting great since then!

Thanks everyone for your help and suggestions, it really encourages you to have a go and try to fix something yourself.

Thanks again, Matt.

 

[MikeApicella]

it probably was a dodgy earth on your dash then,
i was wondering if anyone knew where i could get my hands on an online/digital copy of a haynes manuel.
my sisters been having this problem as well and i said i'd have a proper look at it today and give it a full service but just it would be a useful reference to have.
how exactly were you checking the drain on the instrumental pannel, as i assume im going to need to do this today, and my engine building knowledge is great but electrical is a little rusty..

Cheers guys this is a great thread

Mike

 

[Ziggy122]

SOLVED!: For some reason.

I disconnected the instrument panel on the dash and the drain went from 190 milliamps to 40 milliamps so I was thinking that I will have to get a new instrument panel.

I reconnected the instrument panel and put it back and the drain stayed at 40 milliamps! I have no idea why, but since I disconnected and reconnected the instrument panel the problem has gone! All I can think of is that maybe one of the connections to the panel was dodgy and reconnecting it fixed it, I don't know. The car has been starting great since then!

Thanks everyone for your help and suggestions, it really encourages you to have a go and try to fix something yourself.

Thanks again, Matt.

Could it have been the magical Dash crash issue that happens on rare occassions
Some people get lights and dials staying on after engine off
some dont

I had it where my oil light and temperature guage stayed on after engine off, but due to daily driving it didnt happen to flatten my battery, till one day it cured itself

So well done for persevering with it

Ziggy