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Battery Dead - CTEK question

don0301 said:
Hello

I have no experience with 911's BUT:

I have an Audi RS6 ("smart" battery in the boot) and this car must be charged (trickle charged) by terminals in the engine bay, not on the battery terminals. The reason given is the car "monitors" current use and therefore the battery must not be charged etc directly whilst in situ.

If your car is similar this may be the likely problem. Does your handbook advise?

My previous car was 13 years old when sold still on first battery, my Audi is now 11 years old and the same. I use a CTEK 5 also, but normally only boost charge/condition it sometimes a year.

Hope this helps.

Just checked the handbook and all it says about charging is to disconnect the battery cables first. This MAY be because of the reason you state for your Audi but it doesn't explicitly say why the advice is to remove the cables. Not really much help for constant trickle charging either :dont know:
 
Nor does it explain why some chargers work (even when just connected to the in-situ battery terminals) while the CTEK doesn't. I've sent an e-mail to CTEK HQ with a link to this thread to see if they have any technical comments.
See what they come up with.
This is why I'm automatically suspicious of any car with more than 4 fuses and three wire colours.

Cheers..Ian
 
The S5 refers to the warranty - 5yrs, Bosch S3 - 3yrs.

If its under 5yrs old and you can remember where you bought it..
 
freshy said:
Still non the wiser why neither of my CTEK 5 chargers work on the 911 when they are absolutely fine with every other battery/vehicle I have. It's like something on the car circuitry stops it from going through the sequence.

You are not alone, I have exactly the same issue with CTEK 5 on my 911, when it is fine on other cars!

I would love to figure out why...

After 2 failed Porsche Ctek units in 8 years, have bought the Noco Gernius G7200 7.2 amp which I can't so far fault

also with it's AGM mode, good at charging the Cayenne's large stop/start battery

it's much larger but if I consider it's important, then it was about time for an upgrade


G7200-12V-24V-Automotive-Car-Battery-Charger-AGM-Deep-Cycle-Lithium-Desulfator.jpg


they also have the smaller NOCO Genius G3500UK 6V/12V 3.5 Amp charger

G3500-6V-12V-Automotive-Car-Battery-Charger-AGM-Deep-Cycle-Lithium-Desulfator_1.jpg
 
Could it be an alarm/tracker back-up battery messing with the voltage the Ctek sees? Ie fooling it into determining the car battery is in a different state than it really is?

I use a Halfords conditioner/charger on a two hour timer. Can't see the point in leaving it connected and buzzing for 24 hours. It's worked fine with many cars.
 
Another one here with a problem with their CTEK + 911!

Had an older CTEK version for my Landrover 90 (which used to leak electricity) so bought another one for the 911 and it has exactly the same problem as reported - seems to have 'killed' the bosche silver I put in 3-4 years ago?

Will be watching with interest
 
Personally I don't think batteries are as good as they used to be. Just had a Bosch s5 replaced under warranty on my mini r53 at only 2 years old the original battery it replaced was 12 years old

Also have an s5 in my c5 rs6 and that's only 3 years old and starting to play up to so may need replacing if the charger does not get it going again.

The good thing with Bosch batteries if you get a 5 year no quibble warranty

Winny
 
moorhouse said:
Nor does it explain why some chargers work (even when just connected to the in-situ battery terminals) while the CTEK doesn't. I've sent an e-mail to CTEK HQ with a link to this thread to see if they have any technical comments.
See what they come up with.
This is why I'm automatically suspicious of any car with more than 4 fuses and three wire colours.

Cheers..Ian

Any news back from CTEK Ian?
My Amazon cheapo charger has brought the battery back to life just fine and will be staying on the car now, while the CTEK and all its expensive accessories will be gathering dust...
 
Hi

I use a CTEK on my infrequently driven Bosch S5 Silver batteried 993 and it has been fine for the last 4-5 years.

But this week battery died, replaced without question by Type911 in Bromley.

Berni
 
40Anni996 said:
moorhouse said:
Nor does it explain why some chargers work (even when just connected to the in-situ battery terminals) while the CTEK doesn't. I've sent an e-mail to CTEK HQ with a link to this thread to see if they have any technical comments.
See what they come up with.
This is why I'm automatically suspicious of any car with more than 4 fuses and three wire colours.

Cheers..Ian

Any news back from CTEK Ian?
My Amazon cheapo charger has brought the battery back to life just fine and will be staying on the car now, while the CTEK and all its expensive accessories will be gathering dust...

BUMP

Did you actually hear anything useful from CTEK Ian?

Have finally found my invoice from Euro Car Parts for the Bosche S4 (Oct 17), so the CTEK/Porsche curse has killed it in just two years! - will be seeking a replacement later today
 
I had exactly the same issue. contacted CTEK and they eventually agreed to replace the charger under warranty. Then it happened again about a year later, they again replaced it.

it has been ok since then, but if it happened again I am swapping it out for another make...
 
4b4 said:
40Anni996 said:
moorhouse said:
Nor does it explain why some chargers work (even when just connected to the in-situ battery terminals) while the CTEK doesn't. I've sent an e-mail to CTEK HQ with a link to this thread to see if they have any technical comments.
See what they come up with.
This is why I'm automatically suspicious of any car with more than 4 fuses and three wire colours.

Cheers..Ian

Any news back from CTEK Ian?
My Amazon cheapo charger has brought the battery back to life just fine and will be staying on the car now, while the CTEK and all its expensive accessories will be gathering dust...

BUMP

Did you actually hear anything useful from CTEK Ian?

Have finally found my invoice from Euro Car Parts for the Bosche S4 (Oct 17), so the CTEK/Porsche curse has killed it in just two years! - will be seeking a replacement later today

Pleased you reminded me - no, had nothing back from the CTEK website contact system (sent 2 e-mails) so yesterday spoke with the company I bought my chargers from and they gave me a contact number for the general importer to the UK. Spoke to them yesterday and forwarded the guy a link to this forum - he said he would have a look and get back with any comments. Wasn't something he was aware of so we'll see what he says.

Cheers..Ian
 
Hope I'm not tempting providence here, I have the Ctek 3.8 on my 4S, no issues in almost 5 years of ownership, my car is a toy so doesn't get that much use so is mostly hooked up as it were.
Perhaps the Ctek 5 is the issue?
 
I have the CTEK 5 and an older, less advanced one. the less advanced one has never been a problem, and has always worked when the 5.0 has failed... which is twice now.

I agree I think the 5.0 have an issue
 

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