Good morning,
For half a year now I am the owner of Bravo 1.4 90 km from 2010, equipped with sunroof, gasoline engine.
Since August the car has an irritating problem with the electrical system. The failure occurs while driving. It appeared for the first time on the road made of concrete slabs (practically slow / clutch drive), but it also occurred while driving on the highway and in town. The symptoms are always the same: at the beginning, the dashboard and radio screen gently flashes (dims and shines more strongly). Then the dashboard turns off completely and turns on again (as when the engine is turned off and the key is turned to the first position, all the controls light up). It then happened that the power steering was cut off. At times the car suffocates, as if for a fraction of a second I took my foot off the gas pedal. Twice CHECK ENGINE appeared, which went out spontaneously after 20 minutes. The error codes indicate only low voltage.
I bought a lighter voltage meter. During the problem, the voltage starts to jump between 12-17 volts. It usually stays around 13.9-14.3 without frequent jumps. The car has replaced the battery (new) and voltage regulator (new). The alternator has also been checked. No voltage drops on the cables.
All symptoms appear in accidental circumstances, sometimes 15 minutes after starting, sometimes after an hour of driving. Until now, it helped to unfasten the clamp for ~5 min and further route (even 300 km) I drove without any problem.
Bravo does not drive every day, but several times a week it certainly drives ~5-10 km around town.
Additionally, in the beginning of July I replaced the fan resistor - there was no first cooling run.

Please help me, I will gladly check all the leads.
Video of the moment the problem occurred:
youtu.be/J7PiQo6iQag

Greetings
Grzesiek

Hi

17volts.. does sound like a regulator problem with alternator output


Where was the voltage measured?

The voltage is read inside the car - from the 12V output under the AC control panel. Next time when problem occurs, I will also check the voltage on the battery and the alternator.

Today the situation has been repeated. New information: the voltage jumps on the circuit which operates e.g. lights, radio and lighter. At that time, the voltage on the battery was dropping from about 12.95 to 12.75 (in 5 min). Depending on the mensurement point, voltages are different. After switching off the car and start up again, the battery on the dashboard lit up. After another restart everything was okay

grzesiek12001 said:

Today the situation has been repeated. New information: the voltage jumps on the circuit which operates e.g. lights, radio and lighter. At that time, the voltage on the battery was dropping from about 12.95 to 12.75 (in 5 min). Depending on the mensurement point, voltages are different. After switching off the car and start up again, the battery on the dashboard lit up. After another restart everything was okay

Click to expand...

Is that with or without the engine running ?
If without then that sounds perfectly normal behaviour and 12.75 is. Still a great voltage

If it's without the alternator is definitely broken

Edit just read that from the 12v point in the car ideally you want voltages direct from.the battery

It is with running engine - at the same time I have different voltage inside car and on the battery.

The main battery earth cable is a common failure point on the smaller Fiats. They corrode internally, and can make/break the connection with engine movement. Uneven roads can bring the problem, or just a single bump. When the connection is lost, the alternator loses its sensing for a moment, which could account for the voltage spike.

While checking continuity of the main battery cables, flex them a little.
Also worth getting the battery checked, as it may have an internal short or dead cell.

Thank you, we will definitely check it tomorrow