Technical Any idea what's draining my battery?

[Vynn]

I have a 2013 Abarth and pretty recently I've started running into battery issues.

About 2 weeks ago, I got in the car, tried starting it, all the lights came on but it wasn't triggering the starter.

The battery is new, Feb 2023, I checked the fuses, cleaned the terminals, and thought it was the clutch switch, but it wasn't. After getting it recharged at AutoZone the car started up just fine and has been running for 2 weeks. I had AutoZone run their electric systems test and everything passed.

Today I get in the car and the battery is pretty much dead. Turn the key and lights won't even turn on. The only weird thing is the gauge cluster is making a noise, like the MPH needle tries to move and it flutters in place for a second and stops... Then it repeats this over and over again.

The car is stock, aside from a modification the previous owner did to swap out the head unit with one that can better connect to newer phones.

Any idea what the issues might be?

 

[portland_bill]

A bit of history might help.
Why the new battery in Feb? Was that to replace the original, or had it previously been replaced, and if so, when?
How long have you owned this car?
How long before you bought it, did the previous owner replace the head unit?

A battery going flat is usually caused either by an internal problem, or by a current drain. Aftermarket head units are a frequent cause of such drains, especially if not wired properly. The original unit will have been connected to the CanBUS system. Whilst using a standard DIN connector, the wiring is not to DIN standard. Aftermarket head units will be to the original DIN standard, and should not be connected directly to the vehicle wiring, only through an interface that interprets the CanBUS signals and converts them to analogue.

With everythign off, an ammeter needs to be connected between the battery positive and the main feed to the car. This will show any current. Then the head unit should be disconnected to see if that removes the drain. If that is not the fix, from there the drain can be located by checking varous circuits until one shows the problem.

If the car has 'Blue&Me', that can fail, and a parasitic drain is often a result. The unit can be disconnected, but the body computer will need to be told it is gone. Does the odometer flash?

 

[Vynn]

Bought the car back in March. The new battery from the previous owner was a part of general maintenance along with a lot of other maintenance that was done at a shop (i have the invoices) the head unit was replaced around then too. The previous owner had recently picked it up and was meant to be held onto, hence all the service done, but a larger car was needed for life purposes.

Since I got the car it's been driving flawlessly. I believe the head unit is one that serves as a pretty direct replacement. I do have the original head unit too.

I don't know if it has Blue&Me, it uses android auto and basic Bluetooth phone connectivity.

The odemeter doesn't flash, the battery is that dead. But no idea why the MPH needle was making noise and fluttering when I got in the car, is that something seen before?

I'm ordering a jumper starter and multimeter to test for drains.

 

[Vynn]

I have an update on this.

I was able to perform a parasitic drain test and something is draining 1.35 amps from the battery. Pulling fuse F36 which seems to be connected to the radio will reduce the drain to .2 amps. I forget which fuse specifically, but one connected to the instrument panel also had about .1 amp drain.

Removing the aftermarket radio will reduce the drain to .5 amps. Putting the stock radio back in will raise the drain back to 1.36 amps. So the stereo itself doesn't seem to be the issue :/ The car does have a Blue & Me system, any idea how I can go about diagnosing that without disassembling half the inferior? If the Blue & Is the issue, what are the solutions?

 

[varesecrazy]

Hi

In euro built cars

The odometer dashboard display will flash if B+M fails

Is your odometer flashing?

 

[Vynn]

Hi

In euro built cars

The odometer dashboard display will flash if B+M fails

Is your odometer flashing?

When the stereo was plugged in, no it wasn't flashing. I've removed the stereo and its flashing now. I think were going to look at unplugging the Blue and Me module and see if that makes the drain go away. I believe this aftermarket head unit has its own built in Bluetooth to allow for android auto and such.

Would there be any issues with unplugging the Blue and Me module and leaving it unplugged?

 

[varesecrazy]

Would there be any issues with unplugging the Blue and Me module and leaving it unplugged?

Potentially flashing mileage
( due to 'incomplete circuit' )

Otherwise probably fine

 

[Pino65]

I have an update on this.

I was able to perform a parasitic drain test and something is draining 1.35 amps from the battery. Pulling fuse F36 which seems to be connected to the radio will reduce the drain to .2 amps. I forget which fuse specifically, but one connected to the instrument panel also had about .1 amp drain.

Removing the aftermarket radio will reduce the drain to .5 amps. Putting the stock radio back in will raise the drain back to 1.36 amps. So the stereo itself doesn't seem to be the issue :/ The car does have a Blue & Me system, any idea how I can go about diagnosing that without disassembling half the inferior? If the Blue & Is the issue, what are the solutions?

I have a FIAT Doblo van and i once changed the radio cassette for one with a modern radio CD. It too drained the battery and upon reading the bumf it
transpires that in some vehicles there is a phenomenon where certain terminals need to be swapped to prevent battery drainage and so it was with mine. Hope this helps?

 

[Vynn]

Another update, so far it seems like we solved the issue. It was a combo of the blue and me going bad plus shaky modifications done to the harness for the stereo that caused both the stock and aftermarket radio to drain the battery. Why it took a few months to show problems? Couldn't say.

We pulled the blue and me first and saw the drain go from 1.36 amps to 1 amp. After repairing the harness and putting the stock radio back in the drain went down to .002 amps. We tried testing it with the Blue and Me reinstalled and it would either cause a .2 amp drain or a .7 amp drain. Opted to just leave the blue and me out. Stock radio sounds way cleaner too.

Also for the USA Abarth the Blue and Me unit is behind the glove box. Remove that paper cover beneath the glove box and its right there, with the right tools you can unscrew it from the cage not having to remove anything.