Blinking red battery indicator

[car_noob]

Hi all! I've just bought Seat Leon 2008 a couple of weeks ago, and the last weekend the red battery indicator started to blink on the panel. Also, the clock (and the last trip mileage) is reset every time I turn the engine off.

I checked the voltage with a multimeter, and it showed less than 12V. So I was hoping that that is the reason. I charged the battery, and it was 12.92V after it. But unfortunately, the indicator remained blinking and the clock resetting.

I also made some more voltage measurements:
- in the evening right after charging - 12.92V
- the next morning - 12.83V, and after driving to parking (~1km) - 12.78V
- later in the evening - 12.65V, and after driving from parking - 12.77V

As you can see, there's ~0.1V drop during the night and the same (even a little bit more) during the day. I suppose it might be a sign of a bad/old battery, that it's just not keeping the charge? There's also a small temperature difference between evening/morning, but it's only ~5 degrees celsius, so I think it shouldn't impact so much, right?

Also, I checked the voltage with the engine running, and it was 14.27V. So if I understand correctly, the alternator works well and is not the root of the problem, right?

I also checked the fuses and I found one blown. But it's "Headlight washer system" fuse (according to the manual), so I suppose it shouldn't be connected to the resetting clock... Also, I tried to swap this blown fuse with "12 V socket" fuse (both are 20A, and it didn't change anything.

So I wonder what can be the root cause of the problem? If it's the battery - then why didn't anything change after I fully charged it?

 

[380bhpdaily]

Normally when the battery light flashes it’s because of the alternator voltage. However I see you’ve tested it and the voltage was 14v which is strange. I would check the wiring from the alternator isn’t burnt or damaged.
The chances are it’s the alternator on its way out. When you got 14v we’re all the lights off on the car and when you got 12v the lights were on and drivers door open that would show a drain on a bad alternator too.

 

[car_noob]

Normally when the battery light flashes it’s because of the alternator voltage. However I see you’ve tested it and the voltage was 14v which is strange. I would check the wiring from the alternator isn’t burnt or damaged.
The chances are it’s the alternator on its way out. When you got 14v we’re all the lights off on the car and when you got 12v the lights were on and drivers door open that would show a drain on a bad alternator too.

Thanks for replying! So I'll test the alternator with some load (lights/radio/air conditioning) to check it more.
But can the alternator also be a cause of the clock being reset?

 

[car_noob]

No that’s not something I’ve ever seen or heard about. Have you checked he battery cables are tight on the battery? Almost sounds like one cable might be loose and is breaking connection while you drive.

Yes, the cables are tight and the battery terminals are clean.

I checked the alternator more. When the engine started, the voltage dropped for a moment to ~11V and then to ~14.2V (no load), and it grows a little if to increase revs. With lights and air conditioning, the voltage remains about the same 14.2V

 

[Chris Bartram]

Yes, the cables are tight and the battery terminals are clean.

I checked the alternator more. When the engine started, the voltage dropped for a moment to ~11V and then to ~14.2V (no load), and it grows a little if to increase revs. With lights and air conditioning, the voltage remains about the same 14.2V

I'd suspect that your alternator may be a bit intermittent. Maybe the regulator is playing up, or perhaps the brushes/slip rings are worn. Was the 11V when cranking, or after it fired?

 

[car_noob]

I'd suspect that your alternator may be a bit intermittent. Maybe the regulator is playing up, or perhaps the brushes/slip rings are worn. Was the 11V when cranking, or after it fired?

11V was when cranking, and then it went back to ~14.2V

 

[Chris Bartram]

11V was when cranking, and then it went back to ~14.2V

Ah, ok. 11v cranking sounds reasonable. Could you put your meter on something like the cigarette lighter so you can keep an eye on it, see if the 14v is steady? Also, could you get the codes read, it might give you a clue.

 

[RUM4MO]

Which engine type is in this car, TDI engines move about quite a bit and can break or partially fracture the control wire to the alternator.

Ideally to check cranking voltage you need to use a moving coil ie analogue voltmeter, digital meters response is just to slow to give you a good idea of what the minimum cranking voltage - I'd expect it would go as low as 9V with a good battery, if the battery is aged it might be dipping momentarily down to maybe 7V and that will not support the clock and fuel computer, so they will get reset.

Edit:- maybe as I've had to become an "addict" of what the present voltage at the 12V power socket is at all times, I suggest that you buy a cheap plug in 12V DVM that you can leave in the 12V power socket and keep an eye on things until it has been resolved. If the alternator has issues like worn or sticking brushes or slip rings, that should show up on this cheap plug in 12V DVM which tend to get sold on ebay etc for round about £5 in UK money delivered - from China.

 

[Chris Bartram]

Which engine type is in this car, TDI engines move about quite a bit and can break or partially fracture the control wire to the alternator.

Ideally to check cranking voltage you need to use a moving coil ie analogue voltmeter, digital meters response is just to slow to give you a good idea of what the minimum cranking voltage - I'd expect it would go as low as 9V with a good battery, if the battery is aged it might be dipping momentarily down to maybe 7V and that will not support the clock and fuel computer, so they will get reset.

Edit:- maybe as I've had to become an "addict" of what the present voltage at the 12V power socket is at all times, I suggest that you buy a cheap plug in 12V DVM that you can leave in the 12V power socket and keep an eye on things until it has been resolved. If the alternator has issues like worn or sticking brushes or slip rings, that should show up on this cheap plug in 12V DVM which tend to get sold on ebay etc for round about £5 in UK money delivered - from China.

That's all good and relevant advice.

Also, have you had the battery tested? Usually, these days, they just fail, but it is possible that the voltage might be collapsing under load, and as stated above, a digital meter might not be quick enough to see that.

 

[car_noob]

Thank you all for the advices!

Ah, ok. 11v cranking sounds reasonable. Could you put your meter on something like the cigarette lighter so you can keep an eye on it, see if the 14v is steady? Also, could you get the codes read, it might give you a clue.

So I did it, checked the voltage from the cigarette lighter, and it was somewhere about 14.13V - 14.17V. I had lights and air conditioning on max. It was quite steady I'd say.
I noticed a few times it dropped to about 12V, but it was just a moment and it immediately came back to 14. But I'm not sure if I just didn't move a multimeter end a little bit at those moments.

I should get the codes reader the next week and will check the codes. I hope there'll be something help

Which engine type is in this car, TDI engines move about quite a bit and can break or partially fracture the control wire to the alternator.

Ideally to check cranking voltage you need to use a moving coil ie analogue voltmeter, digital meters response is just to slow to give you a good idea of what the minimum cranking voltage - I'd expect it would go as low as 9V with a good battery, if the battery is aged it might be dipping momentarily down to maybe 7V and that will not support the clock and fuel computer, so they will get reset.

Edit:- maybe as I've had to become an "addict" of what the present voltage at the 12V power socket is at all times, I suggest that you buy a cheap plug in 12V DVM that you can leave in the 12V power socket and keep an eye on things until it has been resolved. If the alternator has issues like worn or sticking brushes or slip rings, that should show up on this cheap plug in 12V DVM which tend to get sold on ebay etc for round about £5 in UK money delivered - from China.

It has 1.6 petrol engine, not TDI.
Do I understand correctly, that if it was the battery dipping to 7V causing the clock to reset, then the clock would reset when starting the engine? Because now the clock resets when I turn off/turn on the ignition.

Thanks for the advice, I'll check these 12V voltmeters, it might be helpful!

That's all good and relevant advice.

Also, have you had the battery tested? Usually, these days, they just fail, but it is possible that the voltage might be collapsing under load, and as stated above, a digital meter might not be quick enough to see that.

No, I haven't had the battery tested. I'm not sure if it's even possible here Do you mean, that the battery can drop the voltage for short moments, that the digital multimeter won't catch?

 

[car_noob]

Also one more thing. A couple of days before the battery indicator started flashing, the "check engine" indicator became lit while driving. I wonder if it's not connected to the battery indicator issue
I hope checking error messages the next week will shed some light

 

[martin j.]

Any decent motor factor should be able to test your battery not with a multi meter but a tester that places a load on the battery, this may give a better indication of the batteries health?

 

[RUM4MO]

"It has 1.6 petrol engine, not TDI.
Do I understand correctly, that if it was the battery dipping to 7V causing the clock to reset, then the clock would reset when starting the engine? Because now the clock resets when I turn off/turn on the ignition.

Thanks for the advice, I'll check these 12V voltmeters, it might be helpful!"

Yes there will be a minimum voltage that lots of controllers and clock will work at, if the battery dips below that level, and it will normally have the best chance of doing that when you crank over the engine, then yes when drawing a lot of current from an unhealthy battery during engine starting would force the clock to reset.

I think that my idea that it might be a TDI was a "red herring" as breaking alternator sense/control wiring does not seem to be a Leon issue even for a TDI one - it can be for Ibiza and its similar other marque equivalents though.

Edit:- I think that if this car was scanned using a fully VW Group compliant scan tool it would report any alternator faults, certainly in my wife's 2015 VW Polo CAN Gateway controller there are fields for faults relating to the alternator.

 

[Chris Bartram]

No, I haven't had the battery tested. I'm not sure if it's even possible here Do you mean, that the battery can drop the voltage for short moments, that the digital multimeter won't catch?

Yes, that. Digital meters have to catch up, you can see a needle flick.

 

[RUM4MO]

One of my CTEK chargers is also a tester, so the idea is, you can use it to check the battery health while cranking over the engine. That is a good plan, but, I found that unless the battery was "super fighting fit", the drop in voltage while cranking, took the voltage below the minimum required to power this CTEK in test mode - now that is not too clever a design. The battery in question, was the original in a 2009 Ibiza 1.4 SC and had never shown an reluctance to start - I was just checking out this function on that CTEK, then I used it on my wife's brand new Polo 1.2TSI, it yielded only an average health rating. That was when I wised up and bought a moving coil meter for that sort of check.

 

[car_noob]

I've been checking the battery voltage for the last couple of days, and it keeps steady at about 12.7V (after the day/night without driving).
One thing I noticed yesterday: the battery indicator started blinking after about 10-15 seconds after starting the engine, not immediately like it was before
I hope I'll be able to read the error codes the next week, and it'll give some more information.

 

[car_noob]

Hi all! A small update. Last weekend I went for a short trip, and the indicator was blinking, but not all the time but periodically. It was like a few kilometres blinking - then not blinking, then blinking again and so far. And after about 15km it stopped blinking completely, and also the clock stopped resetting. And so far everything looks ok.

 

[car_noob]

Hey all! A new update! The battery indicator started blinking again (and the clock and last trip mileage started to reset after turning off the ignition) But I also noticed a couple more things that are not normal:
- the clock display turns off immediately after turning off the ignition (normally it's lit for about 20-30 seconds after turning off the ignition)
- the clock display doesn't turn on when the door opens (normally, it turns on and is lit for some time)
- the clock display can be dimed quite a lot while starting the engine, sometimes to complete disappearance even
- there's no sound signal if to open the door while headlights are on

 

[Chris Bartram]

Do your interior lights go on and off when opening/closing the drivers door?

 

[car_noob]

Do your interior lights go on and off when opening/closing the drivers door?

Yes, the interior lights seem to work fine: turn on after door opening, turn off automatically about 20sec after closing the door