Electric Bug Help!

Hello,

vor einigen Tagen hatte ich den Effekt, dass mein 97er A4 AFN auf die Funkfernbedienung nicht mehr reagierte. Am nächsten Tag war alles wieder klar. Vorgestern konnte ich nicht starten, weil die Batteriespannung auf 10,9 Volt Leerlauf abgefallen war. Habe also messerscharf geschlossen, dass die Batterie defekt ist, zumal es m. E. noch die erste ist. Neue eingebaut. Ladespannung 14,1 Volt, gestern ging alles tadellos. Heute morgen kmme ich zum Fahrzeug: Radie (Delta mit Bose) läuft. Natürlich kein Starten mehr möglich, weil Batterie wieder unter 11 Volt. Habe dann festgestellt, dass, wenn ich Zündung ausschalte, das Radio ausgeht. Steige ich dann aus und verschließe das Fahrzeug, geht das Radio selbstständig wieder an. Das war's also, dachte ich, warum die Batterie wieder leer war. Also: Batterie en paar Stunden ans Ladegerät und problemlos gestartet und ca. 35 km Autobahn gefahren. Dann die böse Überraschung: Wagen springt nicht mehr an, Spannung bricht wieder komplett ein (Innenlicht geht aus). Jemand hat mir Starthilfe gegeben, sodass ich die 35km wieder problemlos zurückfahren konnte. VoAfter trying the front door, the next attempt: the car won't start, and the battery is showing approximately 11 volts.

'It seems the charging machine isn't working correctly, right? I measured 14.1 volts the first time. By the way, the charging indicator light is also off. Unfortunately, I didn't have a voltmeter handy the second and third times. Could the erratic behavior of the remote control and radio also be related to voltage fluctuations caused by a potentially faulty charging machine?'

Thank you for your help.

Regards,
Martha.

Hello!

'Whoa - what's going on?! Have you checked the quiescent current yet? You'll need an ammeter (a standard digital multimeter will also work). Loosen the battery terminal clamp with the key removed (everything turned off). Then, connect one probe of the meter to the battery terminal and the other to the clamp. Carefully disconnect the clamp, wait a few seconds, and then read the value. It should be in the range of a maximum of 30mA.'

Warning: Disconnecting the battery and then inserting the ammeter can damage the measuring device - it can discharge all the capacitors, which is evident by the sparks when connecting.

Check for water leaks. There's a drain opening under the battery that tends to get clogged (should look similar to the Passat 3B). If the water can't drain, it will find its way into the interior and may reach electronic components. And those don't like water.

Best regards,

Hello,

'Idle current is approximately 10 mA. The issue with the radio has disappeared: the radio now stays off when I lock the car. The battery voltage is currently about 11 volts with no load, but drops to 2.5 volts when I engage the starter. So, I need to recharge the battery first to be able to start the car. Afterwards, I will check the charging voltage. Perhaps the alternator is not charging intermittently, or maybe the alternator brushes are worn out; they have already covered almost 300,000 km.'

The drain holes are open.

Regards,
Martha.

At 300,000 km (approximately 186,000 miles), worn-out alternator brushes are not uncommon.

After a few hours of charging, the battery wasn't fully charged, and over the 35 km distance, the blower motor and possibly the air conditioning system, along with the radiator fans connected to the battery, were likely drawing power. Without charging from the alternator, the 11V reading makes sense.

Please fix this as soon as possible. Car starter batteries can only handle a few full charge cycles, and they definitely can't tolerate frequent deep discharges.
And then there's the radio, which represents the second area you need to address. Is the TIM function active?

At 300,000 km, worn-out alternator brushes are not unlikely.


Sure, that could be, but how do you know about the 300,000 km?

If the carbon brushes are lifting, the charging indicator light should also illuminate, right? At least, that would happen if the excitation voltage is applied and no output current is produced?

Nebelwerfer_TDI wrote:

Sure, that could be the case, but how do you know about the 300,000 km?

1st Grade Elementary School; Subject: Reading .

Martha wrote:

Perhaps the alternator is not charging intermittently, or maybe the alternator brushes are worn out, considering they have already run for almost 300,000 km.

Quote:

If the carbon brushes lose contact, the charging indicator light should actually illuminate, right?

From my own experience, I know that this doesn't necessarily have to be the case. The LED only indicates the voltage difference between terminal 15 and D+ (?), but not the actual flow of current.

Hello everyone,

habe gerade mit einem Starthilfeapparat mit eingebauter Minibatterie problemlos anlassen können. Habe das Gerät an die Polklemmen geklemmt und fertig. Damit dürften Masseprobleme ausgeschlossen sein, schließlich nimmt der Strom aus dem Appart den gleichen Weg wie der aus der Batterie. Habe leider kein Amperemeter für hohe Ströme, habe aber über den Spannungsabfall zwischen Ausgang Lichtmaschine und Polklemme Batterie (20mV) erkennen können, dass Strom aus der Lichtmaschine in Richtung Batterie fließt. Das ist aber wohl noch kein Beweis dafür, dass der Strom auch zum Laden in die Batterie fließt, weil vom Polschuh weiter verzweigt wird. Habe ein Voltmeter direkt an den Polklemmen angeschlossen und während einer ausgiebiegen Probefahrt beobachtet. Die Spannung an der Batterie lag stets zwischen 13,8 und 14,2 Volt. Allem Anschein nach ist also alles in Ordnung. Trotzdem scheint die Batterie nicht geladen zu werden (wie gesagt: Aufschluss könnte hier nur ein leistungsfähiges Amperemeter geben, was ich leider nicht habe. Fummeln möchte ich da nix, denn wenn mir da bei laufendem Motor der Shunt abraucht, und die Lima ohne Batterie läuft, ist sie danach bestimmt hin, wenn nicht noch ein paar Steuergeräte).Ist die neue Batterie von A'U ist irgendwie kaputt und nimmt einfach keinen Ladestrom auf? Habt Ihr sowas schon mal gehört? Ich habe die Batterie jetzt ausgebaut und am Ladegerät. Mir fällt auf, dass aus der Zelle am Minuspol als einzige keine Blasen aufsteigen? Ist Is that normal?
Another theoretical possibility is that the internal resistance of the alternator suddenly becomes so high that it can no longer produce a reasonable charging current. However, this is contradicted by the fact that the voltage remains consistently between 13.8 and 14.2 V once the engine is running, regardless of how many consumers I switch on, which means the load resistance remains relatively low.

Die andere Sache mit dem Radio scheint mir tatsächlich eine andere Baustelle zu sein, die jetzt auch nicht unbedingt höchste Priorität hat. WaWhat is TIM?

I am grateful for any helpful suggestions.

Regards,
Martha.

Hello!

Martha wrote:

The new battery from A'U seems to be broken and isn't accepting any charge. Have you ever heard of anything like that? I've now removed the battery and connected it to the charger. I've noticed that only the cell at the negative terminal isn't producing any bubbles? Is that normal?

Try to find out when the battery was manufactured. Any markings (if present) are usually stamped on the terminals or embossed on the casing.

It's quite common to end up with a product that's been sitting on the shelf for a long time. In hardware stores (which I also consider to include places like ATU), fully charged batteries often sit on the shelves for months and, of course, don't receive any maintenance in the form of recharging.
Unfortunately, dry-cell batteries are now almost exclusively available in specialized stores. They are filled with acid only at the time of purchase, which makes them virtually shelf-stable.

Ideally, it would be best to control the acid concentration, if possible.
A battery test can also be performed in a well-equipped workshop. The test should, of course, be carried out under load (there are devices that operate without significant load!). A DC clamp meter should also be available there.

BYE
TDI mechanic.

Hmm,

"As you correctly point out, you can't necessarily conclude from the voltage alone that the battery is actually charging. For example, with an oxidized battery connector, the charging voltage may be present, but only a very limited current flows into the battery due to the high resistance. Since you're already mentioning measuring the voltage drop, I believe you have sufficient basic electrical knowledge to have already checked such things yourself."

Two points, in my humble opinion, are at least worth investigating:

- The multimeter calculates an average value of the measured voltage. For example, if a diode in the alternator regulator is defective, the voltage waveform viewed with an oscilloscope will appear far from ideal. If possible, examining the voltage with a portable oscilloscope would provide valuable information about the condition of the regulator.

- The battery may have a defective cell, or even a broken internal terminal connector. This is not uncommon, as the compressed lead is very porous. In our company, we use several thousand 12V battery packs, and there is always a certain percentage of failures, even with high-quality brands.
I completely agree with tdi-schrauber on all points. Furthermore, it's unlikely that you'll find lead-calcium batteries, which are recommended for the LL concept and will likely be in higher demand in the future, readily available with a pre-charge.

If necessary, you can also test the battery's capacity yourself using a headlight bulb.

TIM = Language memory for traffic announcements.
The radio, with its adjustable pre-tuning time, receives and stores all available announcements each day before the start of the journey.

Hello everyone,

Here's an update on the topic: 1) Transition resistance at the terminal clamps: I was concerned that I was measuring the voltage directly at the battery terminals themselves, rather than at the terminal clamps.

2) Basic knowledge of electrical engineering: I'm a little proud of this one. It's been a while, but at some point, I was an electrical engineer. Before that, I was a telecommunications installer .

3) The issue with the digital or analog voltmeter, or with using 'Oskar' (presumably a device), should be considered. I could potentially test this in a stationary setting using 'Oskar' if necessary. However, I don't think it will reveal much, as the battery's capacitance is likely to smooth out any peaks. A test drive with 'Oskar' is more difficult due to the length of the cable reel.

3) 'Shelf-sitters': I think we're on the right track here: The ATU battery had a sticker on it that allowed you to mark the years 2003 to 2005 as the initial date of use.
I also did some searching on Google and made an interesting discovery regarding the voltage of individual cells by simply measuring the voltage from 'acid to acid': The cell that wasn't gassing is actually not being charged; it has a noticeably lower cell voltage than the other five. Presumably, this could also be verified by measuring the acid density. However, I can't find my acid density meter anymore. So, I returned the battery to ATU yesterday evening and received a new one without any problems. Now, I can mark the years 2005 to 2007. I've temporarily connected it to the charger. It has a higher charging current, and all the cells behave the same: the same voltage, and none of the cells are gassing.
So, I'm assuming it was the battery. I'll keep you updated if it turns out not to be the battery.

4) Radioproblem und TIM.: TIM hat dieses Delta m. W. nicht. Im Moment verhält sich auch alles normal. Trotzdem mache ich das Radio von nun an sicherheitshalber immer selbst aus. Mit dem Komfortsteuergerät hatte ich ohnehin von Anfang an ein paar Problemchen: Öfter mal habe ich den Wagen morgens mit ganz oder teilweise geöffneten Fenster vorgefunden. Beim Freundlichen meinte man, das könne nur daran liegen, dass ich entweder beim Aussteigen mit dem Handballen auf die Tasten gekommen bin oder der Schlüssel in der Hosentasche so unglücklich lag, dass die Komfortöffnungsfunktion ausgelöst wurde. Das hat mich nie so richtig überzeugt und so habe ich das Steuergerät so umprogrammieren lassen, dass Komfortöffnen und -schließen abgeschaltet ist und die Fensterheber stromlos werden, sobald Zündung aus ist und eine Tür geöffnet wird. Seit dem sind die fenster immer zu geblieben. Ein Kollege hatte bei seinem Seat Leon auch ab und zu so merkwürdige Spinnereien der ZV. Das kann dann immer gelöst werden durch Ziehen der entsprechenden Sicherung. So iThat's just the way it is with modern technology.

Martha wrote:

2) Basic knowledge of electrical engineering: I'm a little proud of this. It's been a while, but at some point, I was an electrical engineer. Before that, I was a telecommunications installer

.
Then we are on the same level . I used to be an electrical systems installer and energy systems electrician .

Quote:

3) The issue with the digital or analog voltmeter, or Oskar, should certainly be considered. I could potentially check this with Oskar if necessary, while it's stationary. However, I don't think it will reveal much, because the battery's capacitance is likely to smooth out any peaks in most cases. A test drive with Oskar is, of course, more difficult due to the length of the cable reel.

Sure, it will compensate for the missing rectifier pulses. However, it might lack charging power . But I would postpone that for now; the new battery will probably fix it.

Quote:

4) Radio problem and TIM: As far as I know, TIM doesn't have this feature. Currently, everything seems to be working normally. However, from now on, I will always turn the radio off manually, just to be safe.

I'm not familiar with the specific Audi parts, but my VW Delta has this feature. Even if you manually turn off the radio, it still receives the signal at the programmed time, but without displaying anything on the screen. It's like a programmable video recorder.

I only mentioned that because that's exactly what you'll find in the VW troubleshooting documentation regarding inexplicable battery failures in the diagnostic tree. Just like control units that repeatedly wake up, which then activate everything else in the vehicle. Some control units don't activate until 1-2 hours after the vehicle is turned off. The diagnostic tree is about 30 pages long, so you can spend a lot of time finding such leaks. The more control units and buses there are on board, the more complex it becomes.