Good afternoon,

 

My Wife's Octavia STOP/START mk3 1.4 tsi suddenly wouldn't start on the drive a few of days ago. I found out you could check our the battery Percentage by pressing some buttons on the Dash.

 

When i checked it the battery said SOC 10% and then, for the first time, an error on the dash to say 'Low Battery'

 

I believe the car is still on original battery, we've had it 6 years and not had to replace it in that time - the Car is a 9 years old now.

 

After having the battery replaced the car fired up perfectly and SOC battery check was showing 90 %.

 

Went out for 20 mile drive - checked battery - now showing 80% but still wasn't too concerned.

 

Did another 20 miles today and it's dropped to 70% - so now i am concerned there is something else wrong? 

 

Does anyone know what SOC to expect on a new battery? I am now thinking it could be the alternator dying, not the battery itself?

 

Has anyone experience this issue? Is it normal for the SOC to drop and then stabilise or should it be reading 100% after being charged after a long journey?

 

Thank you

 

Edited 29 August, 20223 yr by peugeot_205_gti

Do you have stop/start ? if you do, was the new battery coded to the car ? 

Hi, it is indeed stop/start - just edited post to make people aware, thanks.

 

IHalfords fitted it on my drive, is this something that should have been done when installing? Anyway I can check? Is it something i can do myself?

 

When i first drove off it had errors to say start/stop not working but after a single drive the warning went away

 

Thanks again

Edited 29 August, 20223 yr by peugeot_205_gti

OK so was the battery probably wasn't re-coded to the car, that means the computerised charging schedule doesn't know it's a new battery and will be trying to charge to the old battery specs, you need to get it re-coded with VCDS/OBD11/Carista 

Edited 29 August, 20223 yr by nige8021

28 minutes ago, peugeot_205_gti said:

Good afternoon,

 

My Wife's Octavia STOP/START mk3 1.4 tsi suddenly wouldn't start on the drive a few of days ago. I found out you could check our the battery Percentage by pressing some buttons on the Dash.

 

When i checked it the battery said SOC 10% and then, for the first time, an error on the dash to say 'Low Battery'

 

I believe the car is still on original battery, we've had it 6 years and not had to replace it in that time - the Car is a 9 years old now.

 

After having the battery replaced the car fired up perfectly and SOC battery check was showing 90 %.

 

Went out for 20 mile drive - checked battery - now showing 80% but still wasn't too concerned.

 

Did another 20 miles today and it's dropped to 70% - so now i am concerned there is something else wrong? 

 

Does anyone know what SOC to expect on a new battery? I am now thinking it could be the alternator dying, not the battery itself?

 

Has anyone experience this issue? Is it normal for the SOC to drop and then stabilise or should it be reading 100% after being charged after a long journey?

 

Thank you

 

Hello, as well as the probable issue of the new battery not being coded in to the cars system, be aware that the charging system will not normally allow the alternator to charge the battery to 100% - this is to allow capacity in the system for regenerative charging.

70-80% should be normal, probably lower on shorter trips.  Keep an eye on the SOC. Do you have access to a good multimeter or alternator tester? 

Edited 29 August, 20223 yr by Warrior193
extra comment

Is the new battery EFB or AGM - is it the same type and Amp Hours rating as the old one?

21 minutes ago, nige8021 said:

OK so was the battery probably wasn't re-coded to the car, that means the computerised charging schedule doesn't know it's a new battery and will be trying to charge to the old battery specs, you need to get it re-coded with VCDS/OBD11/Carista 

 

I remember seeing the Halfords guy plug in something just under and to to right of the steering wheel, does this suggest that he has re-coded the battery?

 

Thanks again

16 minutes ago, Warrior193 said:

Hello, as well as the probable issue of the new battery not being coded in to the cars system, be aware that the charging system will not normally allow the alternator to charge the battery to 100% - this is to allow capacity in the system for regenerative charging.

70-80% should be normal, probably lower on shorter trips.  Keep an eye on the SOC. Do you have access to a good multimeter or alternator tester? 

 

thank you, i don't have access to any testing equipment at the moment unfortunately. 

 

I'd never checked SOC before we had this issue so i didn't know what normal reading should be. Hoping it stays at around 70% then but we will be checking after each trip.

 

Do you think if it goes under 50% I'll need to get it to a garage before it doesn't start? Thank you

 

14 minutes ago, Warrior193 said:

Is the new battery EFB or AGM - is it the same type and Amp Hours rating as the old one?

 

Battery is AGM - not sure if same Amp hours as previous battery  unfortunately. 

 

This is the battery that has been installed https://www.halfords.com/motoring/batteries/car-batteries/halfords--096agm-start%2Fstop-agm-12v-car-battery-5-year-guarantee-548638.html?_gl=1*1fif13e*_up*MQ..&gclid=CjwKCAjwx7GYBhB7EiwA0d8oe95kxIQM98orH8Rpr5qw2_b_lzy7cPzfs1Jurh6p3m_RQ3u1bvmeqBoC9jsQAvD_BwE

 

Thanks

25 minutes ago, peugeot_205_gti said:

does this suggest that he has re-coded the battery

Very likely, yes.

Keep an eye on it; there may be a charging fault, or there may be a parasitic drain on the battery from some connected item with a fault.

Or it may just be normal. 

Probably a good illustration of why they removed the state of charge display later; caused too much anxiety.

 

 

In a minor fit of pedantry, the battery isn't coded to the car, the car is coded to the battery.

There is nothing at all inside the battery that could harbour a code.

Edited 29 August, 20223 yr by Breezy_Pete

2 hours ago, peugeot_205_gti said:

 

Battery is AGM - not sure if same Amp hours as previous battery  unfortunately. 

 

This is the battery that has been installed https://www.halfords.com/motoring/batteries/car-batteries/halfords--096agm-start%2Fstop-agm-12v-car-battery-5-year-guarantee-548638.html?_gl=1*1fif13e*_up*MQ..&gclid=CjwKCAjwx7GYBhB7EiwA0d8oe95kxIQM98orH8Rpr5qw2_b_lzy7cPzfs1Jurh6p3m_RQ3u1bvmeqBoC9jsQAvD_BwE

 

Thanks

The 096 is likely to be larger Amp Hour capacity than your original battery - but that's not a bad thing.

If you are ever going to be in the Wimbledon area, PM me and I could do a quick check of your alternator output.

On 29/08/2022 at 16:45, peugeot_205_gti said:

 

I remember seeing the Halfords guy plug in something just under and to to right of the steering wheel, does this suggest that he has re-coded the battery?

 

Thanks again

Not nessasarily, they did that with mine, plugged a gadget into the diag port - this just gave the car some power to keep settings whilst the battery was disconnected. Made a right mess of it and then drove off. Blew the fuse to the port which turns out is the same fuse as the light switch - took me ages to work out. Had to take it to Halfords Autocentre to get new battery coded.

Yeah, The retail store offering will probably get your battery fitted ok, but I would not rely on then doing any vehicle specific coding etc. They just don't have the expertise or tools or experience or knowledge. It is possibly unfair to think they would.  If you need a battery fitted and a near a retail store - sure. But plan to visit a technician / auto centre etc after to code or adapt to vehicle. Or visit the auto centre or independent garage in the first place.  But Halford retail stores can be handy especially at weekends and evening hours are decent.....