911.1 Battery Issues for Infrequent Driver

ravlondon · Dec 4, 2022

Hi,

Due to work and other reasons my 991 can go weeks without usage. I had a period of near a month with no use and it was dead, had to use the manual key (which was a pain itself) to open the door and then boost to pop the bonnet. Managed to jump and drove it for a bit and put it on a trickle charger for a day however after a few days its back to dead again

. I suspect the batter (porsche OEM) is gone. I wanted to know.

1. What is best non-OEM battery to go for - I feel the Porsche ones in general are not great. I heard Bosch S5 is solid - thoughts, anything better?

2. Does non-OEM battery still affect Warranty. I am currently out (just) but might renew?

3. Anything else I can do to keep the charge in battery given its parked up on the driveway?
Txs
Rav

salisbees · Dec 4, 2022

Just a thought….…. I own a 991.1 and have done since new in 2013, use it irregularly and it is still on the original battery ??. However, I do keep it on a battery charger having been told at purchase that because of the electronics it would discharge in about two weeks if not used. The thought is a C-TEK MXS5 will cost around £80 and, if you have electricity available, will provide a better. Solution and keep your battery in good conditio.

drangular · Dec 4, 2022

3. When not in use leave it connected to an ‘intelligent’ battery conditioner, eg. CTek, all the time. This will maintain the battery in good condition for when it’s needed.

ravlondon · Dec 4, 2022

Sorry should have said, I have a CTek unit but my car is parked on driveway, I dont have a garage.

Is there an way to wire it up such that its maintaining the battery but not through the hood or any other solutions. I was looking at solar but mixed opinions about this and not sure how much use right now.

salisbees · Dec 4, 2022

Mine is also on the drive when in use and. I still use the charger, you can get a 2m extension (making 3m in total) which allows you to close the bonnet and still lock the car. Hopefully you can get close enough ????

drangular · Dec 4, 2022

CTEK supply a fly lead you can permanently connect to the battery ( + ve ) and the earth post close to the near side suspension top (-ve) . The way to do this is illustrated in the manual. CTEK also supply extension leads with ‘Comfort Connectors’ which you can run from the fly lead through the gap in the plastic/rubber bulkhead covering by the wiper and onto your CTEK unit. You then have to connect the CTEK to a power source, preferably mains power from the house. Using this routing enables closure of the frunk lid and you are able to lock the car. The issue then , for you, is how to get power to the CTEK and how to protect the CTeK unit from the weather. One option for the latter would be to place the CTEK unit in the frunk and run the power extension cable to the outside of the car via the same route described above.

ravlondon · Dec 4, 2022

I see. This could work. I need to get power available outside, I have my electrician coming around next week to install an outside IP66 waterproof sockets so with the method you describe above this should all be do-able and safe right? I think ...

salisbees · Dec 4, 2022

The post from drangular covers the complete set up you need and there are no issues with fully closing the boot (frunk) or locking the car. To drive away all you need to do then is to disconnect the fixed fly lead and drive away and on return re plug it in. So simple, no problem!

Carlton · Dec 4, 2022

My 911 wouldn’t fit in the garage so routed some thin electrical cable to the car and powered the CTEK trickle/ conditioner charger via the passenger footwell 12volt socket. The cable is thin enough to be channelled via the bottom of the passenger door (near the front edge).

I had an outside power socket at the back of the house and changed the cable through a long tube waterproof hose so I could channel the lead/hose below the gravel around the house then bought a waterproof box to put the lead into when not in use. Its been work fine for over a year.

drangular · Dec 4, 2022

ravlondon said:
I see. This could work. I need to get power available outside, I have my electrician coming around next week to install an outside IP66 waterproof sockets so with the method you describe above this should all be do-able and safe right? I think ...

Your electrician will be able to advise on the safety of the arrangement I described.
I have the advantage of being able to put my car in my garage so I can get a direct connection to a socket and have no worries about weather. As ‘salisbees’ says the arrangement allows for quick and convenient connection and disconnection. It takes me about 30 seconds to open the lid, disconnect the lead and close the lid again.?????

drangular · Dec 4, 2022

I forgot to say that the fly lead and Comfort Connecter can be fed through the battery cover via the hand hold hole. This means you don’t even have to lift the battery cover to make the connection.
(I’d show you a photos of my arrangement however PCGB makes it so difficult to upload them I’ve given up??)

AndrewCS · Dec 4, 2022

drangular said:
I forgot to say that the fly lead and Comfort Connecter can be fed through the battery cover via the hand hold hole. This means you don’t even have to lift the battery cover to make the connection.
(I’d show you a photos of my arrangement however PCGB makes it so difficult to upload them I’ve given up??)

Like this Cayman installation ... ?

NB ... the battery / earth connector should be selected with M8 eyelets

drangular · Dec 4, 2022

AndrewCS said:
[attachImg]https://www.porscheclubgb.com/forum/download.axd?file=1;1131565&where=message&f=Battery connector.jpg[/attachImg]

drangular said:

I forgot to say that the fly lead and Comfort Connecter can be fed through the battery cover via the hand hold hole. This means you don’t even have to lift the battery cover to make the connection.
(I’d show you a photos of my arrangement however PCGB makes it so difficult to upload them I’ve given up??)

Click to expand...

Like this Cayman installation ... ?

NB ... the battery / earth connector should be selected with M8 eyelets
Thanks Andrew. That’s it exactly.?? Hopefully this will help the OP.

JMR · Dec 7, 2022

ravlondon said:
Hi,

Due to work and other reasons my 991 can go weeks without usage. I had a period of near a month with no use and it was dead, had to use the manual key (which was a pain itself) to open the door and then boost to pop the bonnet. Managed to jump and drove it for a bit and put it on a trickle charger for a day however after a few days its back to dead again . I suspect the batter (porsche OEM) is gone. I wanted to know.

1. What is best non-OEM battery to go for - I feel the Porsche ones in general are not great. I heard Bosch S5 is solid - thoughts, anything better?

2. Does non-OEM battery still affect Warranty. I am currently out (just) but might renew?

3. Anything else I can do to keep the charge in battery given its parked up on the driveway?
Txs
Rav

Firstly - agree with everything everyone else has said about a CTEK - I have one for my 987 and I charge it in the garage through the cig lighter adaptor.

Back to your other questions

1. What is best non-OEM battery to go for - I feel the Porsche ones in general are not great. I heard Bosch S5 is solid - thoughts, anything better?

I've only just replaced a Bosch S5 battery on mine that has been in for about 7years (car is a 07 plate) (this was on the car when I bought it)
Only failed due to age and the fact that I left it without the CTEK plugged in for a few weeks.
I bought another Bosch S5 battery exact same spec and fitted a couple of weeks ago.

2. Does non-OEM battery still affect Warranty. I am currently out (just) but might renew?

I do believe it still does. Mine cost £109 from Eurocarparts, genuine ones are super expensive.

3. Anything else I can do to keep the charge in battery given its parked up on the driveway?

Getting that IP66 socket fitted outside would be your starter.
As said, those solar chargers done really provide enough juice this time of year.

guitarplayer63 · Dec 11, 2022

Everything everyone else said about using the CTEK. I run an extension into the passenger compartment and plug the CTEK into the 12v socket there.

Regarding warranty, Porsche will demand a Porsche battery is fitted so worth considering if you do take up their warranty again. It's an easy job to replace the battery (needs two people though) and you'll get discount on the Porsche battery with your PCGB membership.

Noradavis · Dec 24, 2022

Hi, Due to work and other reasons my 991 can go weeks without usage. I had a period of near a month with no use and it was dead, had to use the ...If you are on the original battery you need a new one. Common occurrence with these cars. Starts fine one day then either dead or strange ...The solution is almost free and counter weighs nothing (software), which turns off the lights after a few minutes if there is no sensed activity on the vehicle.After driving 230 miles I started getting issues with car. First error was in yellow warning "Chassis Error Visit workshop, ...and contact with the road is more important than ever. The 911 Carrera T is a commitment to purism. A conscious release for increased driving pleasure.

geedee · Dec 25, 2022

I am no expert and more than happy to be corrected on anything.
Warranty... I am pretty sure that to be accepted on to the Porsche extended warranty system everything has to be as originally supplied with your Porsche which includes the battery. I also believe that even if the battery is replaced with one of the exact same spec from the original manufacturer, but not through an OPC it would not acceptable under the warranty scheme, as it will be minus the Porsche sticker...?
I have read elsewhere that even the fitment of after-market grills to protect rads/heat exchangers from stone damage can preclude acceptance into the warranty scheme..?
Also worth consideration is that a new battery has to be programmed in to the on board electronics in order that they are "informed" to the extent that the charging regime is then altered to suit a new battery.
I also suspect if on existing Porsche warranty and seeking to renew prior to expiry, it may be possible to do so without having to pay for the 111 point check as a precursor to renewal...?
Again relating to warranty, I do wonder that fitting additional wiring such as the permanent connection of the Ctek plug and socket arrangement for charging, might also have the potential to create warranty acceptance issues..? I use the spring clips supplied with the charger.
Perhaps also worthy of note is that ideally remote charging/jump starting should NOT be carried out using the battery NEGATIVE/EARTH terminal. There is a remote earthing point nearby which is designed for the purpose. The issue relating to the negative battery terminal is that it is used by the on board battery management systems which if connected to an external voltage MAY become confused or damaged to the extent that may create a variety of issues..?
It is indeed a pity that modern vehicles make such high demands on the battery due to complexities in the electrical system, however battery technology has advanced to some degree as have the charging systems.
The 991 and later era Porsche battery`s are likely to be of Advanced Glass Mat (AGM) construction and as such can be expected to have a life span of circa 10 years, though that depends on the duty cycle they are subjected to and semi regular long periods of non usage will likely reduce their lifespan. Also AGM batteries require a different charger/ battery maintainer than old style lead acid batteries the Ctek MXS 5.0 has the facility to be configured to suit AGM battery maintenance.
Driveway electrics... Hmm..? I think I would prefer to have the charger contained within an sturdy enclosure and the low voltage output wires from the charger extended to the car. My thinking being that the risks to animals children might be reduced if they became involved with the trailing lead to the car...?
Another consideration is the length of the trailing lead from the charger output and the size of the cable utilised to avoid confusing the charger`s monitoring system... I have no idea what these limits might be but it seems logical that the closer the charger can be to the battery the better.
IF the decision is to contain the charger in some sort of watertight enclosure I suspect the heat generated by the charger is best taken into consideration in order that the charger does not overheat when working at max output which on the MXS 5.0 is five amps, though with a good condition battery and car electrical system without faults I suspect on an average over time the charger will rarely be running hot...
Just went out to the garage which is currently sitting at circa 9 Deg C , the Ctek is at stage 8 in the maintenance cycle and it is sitting at 15 deg C
Hope this ramble is more helpful than confusing..?
Just thinking in type.

jonathanw · Dec 25, 2022

geedee said:
I am no expert and more than happy to be corrected on anything.
Warranty... I am pretty sure that to be accepted on to the Porsche extended warranty system everything has to be as originally supplied with your Porsche which includes the battery. I also believe that even if the battery is replaced with one of the exact same spec from the original manufacturer, but not through an OPC it would not acceptable under the warranty scheme, as it will be minus the Porsche sticker...?
I have read elsewhere that even the fitment of after-market grills to protect rads/heat exchangers from stone damage can preclude acceptance into the warranty scheme..?
Also worth consideration is that a new battery has to be programmed in to the on board electronics in order that they are "informed" to the extent that the charging regime is then altered to suit a new battery.
I also suspect if on existing Porsche warranty and seeking to renew prior to expiry, it may be possible to do so without having to pay for the 111 point check as a precursor to renewal...?
Again relating to warranty, I do wonder that fitting additional wiring such as the permanent connection of the Ctek plug and socket arrangement for charging, might also have the potential to create warranty acceptance issues..? I use the spring clips supplied with the charger.
Perhaps also worthy of note is that ideally remote charging/jump starting should NOT be carried out using the battery NEGATIVE/EARTH terminal. There is a remote earthing point nearby which is designed for the purpose. The issue relating to the negative battery terminal is that it is used by the on board battery management systems which if connected to an external voltage MAY become confused or damaged to the extent that may create a variety of issues..?
It is indeed a pity that modern vehicles make such high demands on the battery due to complexities in the electrical system, however battery technology has advanced to some degree as have the charging systems.
The 991 and later era Porsche battery`s are likely to be of Advanced Glass Mat (AGM) construction and as such can be expected to have a life span of circa 10 years, though that depends on the duty cycle they are subjected to and semi regular long periods of non usage will likely reduce their lifespan. Also AGM batteries require a different charger/ battery maintainer than old style lead acid batteries the Ctek MXS 5.0 has the facility to be configured to suit AGM battery maintenance.
Driveway electrics... Hmm..? I think I would prefer to have the charger contained within an sturdy enclosure and the low voltage output wires from the charger extended to the car. My thinking being that the risks to animals children might be reduced if they became involved with the trailing lead to the car...?
Another consideration is the length of the trailing lead from the charger output and the size of the cable utilised to avoid confusing the charger`s monitoring system... I have no idea what these limits might be but it seems logical that the closer the charger can be to the battery the better.
IF the decision is to contain the charger in some sort of watertight enclosure I suspect the heat generated by the charger is best taken into consideration in order that the charger does not overheat when working at max output which on the MXS 5.0 is five amps, though with a good condition battery and car electrical system without faults I suspect on an average over time the charger will rarely be running hot...
Just went out to the garage which is currently sitting at circa 9 Deg C , the Ctek is at stage 8 in the maintenance cycle and it is sitting at 15 deg C
Hope this ramble is more helpful than confusing..?
Just thinking in type.

jonathanw · Dec 25, 2022

Have had had my 991.1 for 9+ years and have only done about 25K miles in total. I replaced the battery at about 7 years and have used an Optimax smart charger for most of the time I have had this 911 and would highly recommend it. I had a warranty rejected by a Porsche owned main dealer after having cover for about 4 years as my dashcam was had wired even though a non hard wired connection probably was more dangerous! I also have grills on the front! I have had issues with that dealer, who I had purchased my current car a several ones before! I have for several years used a non Porsche owned official dealer for servicing and have had excellent service with cheaper costs and I suspect that if I had requested a warranty from them that they would have issued it but I have decided to not bother with a warranty.
You can avoid recoding by keeping a 12 volt supply to the car active from either jump leads from another car or a device such as a solid state battery charger. It worked for me on my Porsche and recently on my Range Rover.
The Optimax chargers can have extension leads with waterproof extension cables so the charger can be kept within a garage etc. There are various connectors to either cigarette lighter sockets to semi permanent connectors to the battery terminals.

AndrewCS · Dec 25, 2022

Info ...

I also suspect if on existing Porsche warranty and seeking to renew prior to expiry, it may be possible to do so without having to pay for the 111 point check as a precursor to renewal...? Correct

Again relating to warranty, I do wonder that fitting additional wiring such as the permanent connection of the Ctek plug and socket arrangement for charging, might also have the potential to create warranty acceptance issues..?

My last two cars have - had the permanent connection noted in the pictures above - both covered by extended warranty - both OPC serviced - both had warranty claims honoured without question (connection is visible when the cabin air intake filter is serviced - changed)

Perhaps also worthy of note is that ideally remote charging/jump starting should NOT be carried out using the battery NEGATIVE/EARTH terminal. There is a remote earthing point nearby which is designed for the purpose. The issue relating to the negative battery terminal is that it is used by the on board battery management systems which if connected to an external voltage MAY become confused or damaged to the extent that may create a variety of issues..? Owners operating manual notes this point

Driveway electrics... Hmm..? I think I would prefer to have the charger contained within an sturdy enclosure and the low voltage output wires from the charger extended to the car. My thinking being that the risks to animals children might be reduced if they became involved with the trailing lead to the car...?
Another consideration is the length of the trailing lead from the charger output and the size of the cable utilised to avoid confusing the charger`s monitoring system... I have no idea what these limits might be but it seems logical that the closer the charger can be to the battery the better.
IF the decision is to contain the charger in some sort of watertight enclosure I suspect the heat generated by the charger is best taken into consideration in order that the charger does not overheat when working at max output which on the MXS 5.0 is five amps, though with a good condition battery and car electrical system without faults I suspect on an average over time the charger will rarely be running hot...

I sometimes run this type of external connection to my MY 2000 Audi, using an early model CTEK unit - all CTEK battery chargers are approved for outdoor use to IP65 and IP44 standards, my supply is from an external IP66 rated 13A wall box fed from the garage main fuse box - protected by circuit breakers

CTEK supply suitable extension leads compatible for such ^ use

My sturdy enclosure is an upturned plastic bucket, secured with a brick