Alfa 147, flat battery

Started by giovannidc, October 26, 2016, 07:46:32 PM

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giovannidc

Hi guys,
just moved my car a bit today so i could vacuum the interior.
Fast forward 3 hours later and the battery is flat, the engine does not turn over.
I have to say i do short daily trips to work which are barely 5 minutes each way.
Also, i did get a flat or really weak battery a couple more times.
I went to check the battery status indicator and it is green, meaning it should be fine.
Not sure how old the battery is but how about alternator?
Any ideas?

bazzbazz

Ok, do you own a multimeter? If so check the battery voltage, should be 12.2 or above with everything tuned off.

The colour indicator can be a bit of a hit and miss with batteries, but if you can turn your headlights on at high beam at nite and they are fully bright I would take a guess that its most likely correct. With all headlights on at high beam voltage should still hang around the 12v mark.

If it passes all this I would say the problem is with the starter motor, not the alternator. its simple to check which is the problem, put the battery on charge overnight hook it up in the morning, if it don't start but still shows good voltage, its the starter motor, if it starts, but with engine running doesn't show more than 13V its the alternator.

I have had two clients just this week with the same story as yours, both turned out to be dud starters.

Baz
On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

giovannidc

#2
Hello,
i just tested the battery.
Without switching anything on it's sitting at 12.3V but as i turn the ignition to the ACC position it drops to 10.2 ish.
Also i just tried to see if it drains anything and it's sitting at -0.61 amps.
Dead battery or alternator?

bazzbazz

When you turn it to ACC??  You mean when you turn it to Ignition where all the dash lights come on, or when you turn it to start where the engine is supposed to turn over and start?

If it just to ignition (MAR) and it drops to 10.2 the battery is stuffed, if you are turning it to Start 10.2 is still low.

Do you/friend/neighbour own a battery charger?

If so, disconnect the negative lead from the battery and charge the battery overnite, reconnect in morning and try and start. if it starts, ok, if not, it could be anything from a faulty relay to a stuffed starter motor.

A faulty Alternator will not stop a car from starting if the battery is fully charged, it will just cause it to go flay all the time.
You just simply need to have a fully charged, good condition battery in the car first before you can asses anything else.

And of course make sure both positive and negative terminals of the battery are tight.

Baz
On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

giovannidc

I had my battery tested and it was shot. Basically it would recharge but not have enough CCA to crank properly.
I can tell the difference with the new battery now. The previous one must have been like 3 years old and probably sat unused for a bit too.
Alternator and starter motor are fine.
Thank you for the help! :)

giovannidc

Also, funny how this fixed my ASR warning every now and then. I really think Alfas don't like shot batteries at all.

bazzbazz

On The Spot Alfa
Mobile Alfa Romeo Diagnostic/Repair/Maintenance/Service
Brisbane/Gold Coast
0405721613
onthespotalfa@iinet.net.au

giovannidc

Funny how it used to drive me crazy and it was all in the battery.
Glad this got sorted!