Technical Alternator not charging

[storm634]

Hi guys, I have a 2007 Fiat Panda 1.2 dynamic and the alternator will not charge the battery. If I jumpstart the car it will run for a few seconds quite poorly and then the screen will flicker and cut out.. Before changing the alternator, I want to check out some other bits and after an OBD scan, it is throwing up a U1600 code. Could this issue be key-related? And what else should I look for before changing the alternator? Thanks

 

[koalar]

Been struggling to play the video due to slow connection to the forum

Is that just ignition on

 

[storm634]

Been struggling to play the video due to slow connection to the forum

Is that just ignition on

Yes and there is also a video of it starting up.. is there another way for you to view the video?

 

[storm634]

Yes and there is also a video of it starting up.. is there another way for you to view the video?

I Have found a random disconnected plug which I will send a picture of

 

[koalar]

Not used

Legacy from pre ABS days

 

[koalar]

Post 19 the lights for the battery isn't correct

The battery light should remain on until the ECU detects more than 5.5V from the alternator and 750 rpm

Is there any history to why it was parked up, like a faulty alternator, or is it more likely to be rodent damage to the wire

 

[storm634]

Post 19 the lights for the battery isn't correct

The battery light should remain on until the ECU detects more than 5.5V from the alternator and 750 rpm

Is there any history to why it was parked up, like a faulty alternator, or is it more likely to be rodent damage to the wire

The car was was not run AT ALL from april 2021 to around August last year, after sitting for years the alternator was slightly seized but after it got unseized it did work fine. And there was actually mouse nest in the battery tray. Oops. I just got rid of the mouse nest as I didn’t see any damage

 

[koalar]

Not sure of the path of least resistance to take first

Visual inspection of the alternator and make sure it's pulley is spinning, they can corroded together solid, but it's fairly rare

You could just slap an alternator on and suck it and see

Strange thing is

Post 11 shows the battery light staying on while cranking

Post 19 shows no battery light at ignition on

Faulty rectifier in the alternator should always be the same results

O.2V is correct while cranking as long as you are only using it's own battery the earth lead is fine


Personally I'd check the voltage on the alternator D+ wire at ignition off, ignition on and engine started

Koalar random thoughts | FIAT Panda (Mk3)

You can tell if the coil pack is getting a control signal and giving a good spark like this If one is weeker and the spark does not jump as far than the others it's suspect It is possible to get a jolt if you do something wrong, probably not a good idea if you have a pace maker As long as the...

www.fiatforum.com

Also if you can rev the engine over 4k does it then start to charge

 

[storm634]

Not sure of the path of least resistance to take first

Visual inspection of the alternator and make sure it's pulley is spinning, they can corroded together solid, but it's fairly rare

View attachment 461045

You could just slap an alternator on and suck it and see

Strange thing is

Post 11 shows the battery light staying on while cranking

Post 19 shows no battery light at ignition on

Faulty rectifier in the alternator should always be the same results

O.2V is correct while cranking as long as you are only using it's own battery the earth lead is fine


Personally I'd check the voltage on the alternator D+ wire at ignition off, ignition on and engine started

https://www.fiatforum.com/threads/koalar-random-thought.503176/post-4702194

Also if you can rev the engine over 4k does it then start to charge

Not sure of the path of least resistance to take first

Visual inspection of the alternator and make sure it's pulley is spinning, they can corroded together solid, but it's fairly rare

View attachment 461045

You could just slap an alternator on and suck it and see

Strange thing is

Post 11 shows the battery light staying on while cranking

Post 19 shows no battery light at ignition on

Faulty rectifier in the alternator should always be the same results

O.2V is correct while cranking as long as you are only using it's own battery the earth lead is fine


Personally I'd check the voltage on the alternator D+ wire at ignition off, ignition on and engine started

Koalar random thoughts | FIAT Panda (Mk3)

You can tell if the coil pack is getting a control signal and giving a good spark like this If one is weeker and the spark does not jump as far than the others it's suspect It is possible to get a jolt if you do something wrong, probably not a good idea if you have a pace maker As long as the...

www.fiatforum.com

Also if you can rev the engine over 4k does it then start to charge

Thanks for all your advice today… my next step is to test the voltage on the d+ wire a you mentioned. Had the car running a bit today but it ran terribly with low voltage etc.
thanks again

 

[koalar]

Try fresh petrol and battery

Petrol does go off

Weak battery will cause poor idle and cutting out even with an alternator pumping out 14.1V

 

[storm634]

Try fresh petrol and battery

Petrol does go off

Weak battery will cause poor idle and cutting out even with an alternator pumping out 14.1V

It’s got fresh petrol.. you see I would think the same battery wise but just the other day a fully charged battery was put in to test and it drained it flat. It’s going to be a little while before I can do some more work on the panda, but I’ll bring this thread back up and start looking through some more stuff. Will re-post when I do

 

[DaveMcT]

Fit a known good battery and test the current (with everything off) between battery + and terminal. Ideally clip the ammeter on. Current should fall to near zero after a few minutes. If there is a continuous current (drain), disconnect the alternator main lead at the alternator. It's fiddly and you have to get under the car. If current draw goes away, you have a faulty regulator/rectifier and might as well fit a new alternator. They cost about £90.

Also look for cracks in the alternator case. The iron stator cores corrode and split the whole thing. That's a new alternator job.

 

[storm634]

Fit a known good battery and test the current (with everything off) between battery + and terminal. Ideally clip the ammeter on. Current should fall to near zero after a few minutes. If there is a continuous current (drain), disconnect the alternator main lead at the alternator. It's fiddly and you have to get under the car. If current draw goes away, you have a faulty regulator/rectifier and might as well fit a new alternator. They cost about £90.

Also look for cracks in the alternator case. The iron stator cores corrode and split the whole thing. That's a new alternator job.

Thanks, ive been looking at new alternators anyway, Ive took the old one off twice and put a new belt on so I’m familiar with the procedure, luckily its the non AC one so the alternator is very easy to get out, I didn’t even have to go under the car.. I will try what you said above when I can, I do suspect it’s the alternator. You can get a Ford KA one which is identical for slightly cheaper which is good

 

[koalar]

We are not looking for a parisitic drain

We have no output

Test the D+

No current to the exciter coils no output

And go from there

 

[storm634]

We are not looking for a parisitic drain

We have no output

Test the D+

No current to the exciter coils no output

And go from there

The car has no parasitic draws that I know of even if that couldve been the problem. It did have a black box drawing power which I disconnected

 

[koalar]

Have you managed to find the connector in the link in post 27

It should be somewhere between the battery and engine

 

[storm634]

Have you managed to find the connector in the link in post 27

It should be somewhere between the battery and engine

Not yet, i can’t always access the car.. when i can I’m going to do all the things you have suggested

 

[DaveMcT]

Disconnect alternator wires and your parasitic drain will almost certainly be gone. If the alternator previously had to be unseized, it's probably toast by now. As said earlier the cores corrode. I've had two go that way.

 

[koalar]

Disconnect alternator wires and your parasitic drain will almost certainly be gone. If the alternator previously had to be unseized, it's probably toast by now. As said earlier the cores corrode. I've had two go that way.

Why are we diagnosing a parasitic drain, the battery was flat because the car was stood for a year, this is normal behaviour

We have no output, nothing across the battery terminals

Either the alternator isn't outputting or the excitor isn't exciting, before pulling the trigger on the alternator, I'd check the is current present on the exciter especially since there been a mouse living on top of the battery

 

[storm634]

Why are we diagnosing a parasitic drain, the battery was flat because the car was stood for a year, this is normal behaviour

We have no output, nothing across the battery terminals

Either the alternator isn't outputting or the excitor isn't exciting, before pulling the trigger on the alternator, I'd check the is current present on the exciter especially since there been a mouse living on top of the battery

That is my plan, I do not have to diagnose a parasitic drain because the one I know of has been removed. Dave may be right, the alternator is probably knackered but first we will check if the is current on the exciter. I cannot do it yet but that is what I’m going to do

 

[koalar]

That is my plan, I do not have to diagnose a parasitic drain because the one I know of has been removed. Dave may be right, the alternator is probably knackered but first we will check if the is current on the exciter. I cannot do it yet but that is what I’m going to do

Correct

A brand new battery, disconnect loose approximately 5% a month, an old battery could easily loose two or three times that

A battery is unlikely to survive a year of not being charged, lead acid batteries like to be kept fully charged

If you leave the battery connected its even worse even though the draw waiting for the remote,key and keeping the clock going isn't that much, it has drastic effect on how much is lost each month