Is the battery dead?

[Gabbo]

On 05/12/2022 at 14:33, nta16 said:

 Please note - I am not a mechanic or expert in anything.

Just out of my interest which model Bosch charger have you got, if you want to say?

 

I've got a Bosch C3 charger which has an AGM regeneration mode. It seems to work pretty well as a few hours charging gives good starting performance the next day.

Unfortunately as you state, the damage was already done letting the battery get to zero & leaving it too long.

However, the charger has kept me going without any problems for 18 months & with regular driving everything is fine. I just put it on charge occaisonally if I've not used it for a week.

https://www.amazon.co.uk/Bosch-intelligent-automatic-motorcycles-commercial/dp/B09C925GNQ

 

On 05/12/2022 at 14:33, nta16 said:

Personally I would not be surprised if putting the new battery in good state of charge on the car allows the use of stop/start during or after the first reasonable length and use of the car, but I am often wrong.  After the test I would get all error codes cleared just in case they might confuse the VW computer programs, you might find there are more than expected from having the battery in a low state for so long, or I could again be wrong.

My StopStart has not really worked for 18months with the current battery even during summer when I have no problems starting & no need for charging.

I am driving around 130km (80miles) per day, 4 days a week, so when I using the car, it is warm & has plenty of time to recharge so seems clear the battery is past its best.

 

In the winter when I start the car, the dashboard has many warnings during the first few seconds after starting (ACC Not Available, ABS Error (sometimes), Instrument Cluster resets) so Id expect there were be several DTCs stored for low battery voltage conditions.

However, the car has been to the dealer for service twice in this time (they've checked the battery & told me everything is fine) so either they are not checking or they just assume every car has these & clear them.

 

Its due another service in January 2023, so I will replace the battery tomorrow, leave it to see how long it takes for StopStart to work again & see if they mention it when its serviced.

 

 

Gabbo

 

Edited 6 December, 2022 by Gabbo

[nta16]

Please note - I am not a mechanic or expert in anything.

 

@Gabbo the C3 has done well to keep you going but if the start/stop hasn't worked for 18 months and you get early Xmas lights in winter possibly the car and battery were trying to tell you something, sounds like battery cruelty.

 

If not then there might be something wrong with your car, did the garage test the battery and alternator/charging system, easy for them to do.  Or perhaps you where not connecting the C3 negative lead to the engine earth on your rechargers.

 

If you were charging at below 0 perhaps the C3's electronics did not like it and the battery would not, the instructions I saw for the C3 did not show a winter setting but it kept your battery going so it must have been doing a reasonable job at the very least.  I like the 3.8 amps(?) but  perhaps your battery needed more than a few hours recharging from it sometimes.

 

I am just trying out my latest and by far most modern charger £23.49, I can't stretch to a Bosch label, charging my neighbour's diesel van battery.  Third time in a couple of years IIRC, originally it had sat on the garage floor for 18-24 months because he removed it from the van flat and thought it would not be worth charging.  My old chargers got it back to life and it now alternates with the other battery he has that goes flat from lack of vehicle use.

 

I applaud you getting longer out of your battery by recharging it but not if you have persistent warning lights and messages because of the battery being low, you are lucky you done enough to just about feed the evil VW computer programs an they have not made you and the car suffer more.

 

I think you might notice a difference to the car with your new battery, be interesting to hear.

 

Cheers.

 

[Gabbo]

Battery replaced this afternoon. No problems just a bit fiddly getting the cover & the battery clamp back in place.

 

At the first start after changing the battery, engine started fine (battery must be mostly charged) but there were 3 warning messages on the display & flashing in the cluster:

  - ACC Error

  - ESP Error

  - Tyre Pressure Monitoring Error

After driving 500m the last 2 errors disappeared on their own leaving only the ACC error.

I drove about 3km & stopped to collect the kids.

At the next start, there were no errors & the engine started without any warnings on the display.

 

Just before reaching home (when the cabin temperature had reached the setpoint) StopStart was enabled & the engine stopped while waiting at traffic lights...

Previously there was always a message in the StopStart overview saying "High Power Consumption" which I guess must have been the alternator trying to charge the old battery.

 

So everything seems to be working fine without any "learning/programming" at the moment.

I will report back if I see any differences/problems over the next few days. I've got a 120km round trip tonight.

 

@Giff If you didnt already order your battery I can recommend Galaxus or SwissBatt.ch (ordered at Galaxus & delivery by SwissBatt 2 days later).

[Giff]

Glad it worked. I also replaced it successfully yesterday. Saw the ACC error but then all was fine. Didn't drive though, only let the engine on for a few minutes.

[nta16]

 

 

@Gabbo 500m instead of varoom's 100m, tut, just goes to show how much you abuse that poor battery. 🙃

 

Some will say if you haven't 'coded' the battery in the car could be overcharging it because the car doesn't know it is a new battery and the life of your battery will be shorten, I did not have the new battery 'coded' straight away  but the battery is only about 18 months old so I have no proof, either way.

 

For your new battery when needed hopefully with your experience you will recharge the new battery sooner than later.

 

I would get a scan done to remove any historical codes as I don't trust the over-complex VW computer programs, at the same time as having the battery coded in but I would not lose sleep over it in the meantime, but that's me.

 

Good luck.   

[Gabbo]

Quick status update:

I've done around 1500km since changing the battery.

I've not seen one warning on the dash when starting, and starting has been strong and fast even when left around -5 to -10 during the recent cold days.

Stop start also works robustly & I've even seen "stop start available" in the vehicle status view which I don't think I even saw very often when the vehicle was new.!

 

No signs of problems from not coding a new battery or not clearing the errors.

 

Should have changed it much sooner..!

 

Gabbo

[nta16]

Please note - I am not a mechanic or expert in anything.

 

9 minutes ago, Gabbo said:

Should have changed it much sooner..!

Yes, most likely. 

 

Charging it sooner and fully might have given better results and even longer battery life than you got but you done better than would be expected already - and we're all older and wiser now (well older at least).

 

I think you might be a convert to the importance of the 12v battery to a car especially modern cars and especially with the likes of VW products.  Some say all you need do is drive the car for charging the battery, which is fine if you have shares in 12v car battery manufacturing. 😄

 

Your original battery was originally on a brand new car so should last the longest but given your past achievements and new experience and knowledge I bet you can get even longer out of your new battery. 😉

 

[Gabbo]

Just a quick update for anyone arriving at this topic at a later date.

 

My car has been through the Skoda garage twice since the battery change. for an annual service & brake change & there were no complaints or comments from the dealer about DTCs or requests for battery recoding.

 

So I'd say, if you change like for like the software will "learn" quickly the new behaviour of the battery & doesn't cause any problems.