Citroen C3 1.4i 2005 - Alternator Permanent Fault

[pecemk]

Hello Guys,

I've been struggling with getting this issue solved, been to lot of local car electricians, only thing that they've said was let's replace the alternator,

but something there is not looking right to me. The alternator is charging at proper voltage 14.3-4, but when they connect it to a diagnostic tool they can see fault in
alternator to ecu communication. There's no check or fault showing on dashboard.

Is there something missing here?
Here's a photo of the connector to the alternator, I am seeing there's only red wire here, and there's no green one, is this how it should be on this model, or someone has done something incorrect in the past?

Any thought will help,

Thanks in advance to all who've read this.

[RichardW]

Welcome along

If it's charging and there are no warning lights on, I'd just ignore it?

[xantia_v6]

It is normal for the green wire to be cut off, if you open up-the alternator you will find that pin isn't connected to anything.

Are you getting an engine repair warning?

[shtu]

I have the same problem. It's some sort of looseness in the connector for that single wire. I can unplug it, jump across the gap with a test lead, and the fault can be cleared. That wire is a single-wire linbus connection.

(if jumping the connector doesn't resolve it, there's probably a break in the wire somewhere, check it with a scope.)

It's not a -major- probem, other than the alternator stops being smart and outputs all the volts all the time.

[ozvtr]

There's no check or fault showing on dashboard.

Does the battery light come on when the key is turned to ignition?

Some unscrupulous people blank out fault lamps when they sell their vehicles to make it look like there are no faults. Just saying.

I honestly do not know what the "battery light" is for! I have seen an alternator over charging...no battery light. I have seen alternators not working at all...no battery light. Absolutely dead batteries...no battery light. WTF is it for then? Is the battery light ACTUALLY connected to the charging system? Dunno, I have no proof!
And here you have the alternator putting out more than 14V, the engine ECU whinging that there is a fault, but then not bothering to throw up a fault light on the dash. Hmm par for the course I would say.
Could it be corrosion or lack of continuity of that wire between the alternator and the engine ECU? Yep could be. But the "failure" doesn't seem to make any difference. The alternator is working just fine! And the engine ECU doesn't seem too worried because it's not throwing up a fault light!
Sure, the light blinks when the car goes into ECO mode, but that has NOTHING to do with the charging system!

As long as you have more than 14V at the battery with the engine running, then the alternator is doing it's best. Seems you can not rely on either the engine ECU or the battery light to tell you if there is a fault...or not.
Sorry, I am a technician and engineers are my mortal enemy. LOL!

[pecemk]

Hello guys, thank you all for replying on the subject, I am sorry I was not replying, I was waiting for the scanner to arrive from AliExpress it took 3 months, now I can finally see on my own what is going on

These are faults Alternator related

And yes it is charging good, bit on higher side, I am worrying if this maybe can cause innacurate sensor readings and what not, thats why I want to get it fix.

[pecemk]

It is normal for the green wire to be cut off, if you open up-the alternator you will find that pin isn't connected to anything.

Are you getting an engine repair warning?

Hi, yes with a scanner tool, I can see these

[xantia_v6]

Is there any difference in behaviour if you run it with the control wire disconnected from the alternator?

Has the alternator been replaced? (before or after this fault appeared?)