Along with tyres and tyre pressures, the most common thread topic on the 996 forum is probably flat batteries. I hope this thread helps to collate all the wisdom that is spread throughout the forum. If I have mised anything, pls PM me and I will add it, or just add it yourself. Also, if I have got anything wrong, let me know so I can remove it and people dont short circuit themselves...
1) Battery problems are very common. A combination of less than supercar-standard electronics, a large engine, and lots of modern electronic gizmos to run means the strain on the standard Porsche battery is large. If your battery dies, its not because you are a bad person.
2) Batteries are a consumable. A car driven for 30mins 4-5 times per week might have a battery last 3yrs or maybe more. A car driven less often or for shorter duration will put more strain on the battery as it doesnt get charged enough during a drive, and discharges when sitting idle.
3) A battery that goes completely flat 2-3 times is probably too knackered to carry on living in a 996, even if you charge it up fully. If you do need to charge a completely dead battery, disconnecting it from the car while charging will give it the best chance of rejuvinating to full strength.
4) Do not skimp on battery quality, it will hurt you in the end. A good quality battery (Bosch Silver, Varta, OPC) will always outlast a £30 one from the market, even if they have the same 'rating' (eg 80Ah).
5) Trickle charging is a great way to keep batteries alive if you dont drive that often. The CTEK 3600 is a good option, there are other brands as well (search for CTEK on the forum and other suggestions will come up). If you find the lead on the CTEK isnt long enough to reach your battery, go to Maplin and buy some more wire and connectors for £5, and get the soldering iron out.
6) In a factory spec.996 I believe the cigarette lighter is not always live (it is dead once ignition turned off, so wont deliver current to the battery). So before plugging the trickle charger into it, get a Porsche techy to make it live (1hr labour max) or connect the trickle charger direct to the terminals using the plugs supplied with a CTEK. To check if its live, plug in your SatNav or road angel, get out of the car and lock up. If it stays on...
7) If you park in the street, so cant trickle charge from the mains, there are solar panels that are supposed to trickle charge. Won't be as powerful as a mains trickle charger, but if its your only option...
8 ) The standard drain on a car when 'sleeping' should be in the region of 20-80mA (ignition turned off, locked up and left for 90mins). Faulty Trackers (shorting or their internal battery flat) or other non standard electronics left on will obviously increase this. You cant test this, its need to be a garage with decent electronics diagnostics. If you're interested in how its done, PM me.
9) The car 'goes to sleep' after 4 days of no action. Various systems shut down, including the remote alarm facility. Top tip for unlocking easily: Unlock using the key in the door. Immediately lock it using keyfob remote, then unlock it using keyfob remote. Much easier than unlocking using key and quickly having to jump in car and put key in ignition and turn.
10) If you need to jump start, you need to connect the jump leads to the actual engine (-ve) and a terminal located in the engine bay (+ve). This is shown clearly in your manual. Dont connect jump leads to your battery in the front boot.
11) If completely dead, you wont be able to access your front boot as the alarm keeps the manual bonnet-pull locked. Apparently there is a terminal on the fuse board (think its a 30A fuse) to connect a remote battery to which will let you open the front cover (earthing it elsewhere I guess, having never done it myself)
1) Battery problems are very common. A combination of less than supercar-standard electronics, a large engine, and lots of modern electronic gizmos to run means the strain on the standard Porsche battery is large. If your battery dies, its not because you are a bad person.
2) Batteries are a consumable. A car driven for 30mins 4-5 times per week might have a battery last 3yrs or maybe more. A car driven less often or for shorter duration will put more strain on the battery as it doesnt get charged enough during a drive, and discharges when sitting idle.
3) A battery that goes completely flat 2-3 times is probably too knackered to carry on living in a 996, even if you charge it up fully. If you do need to charge a completely dead battery, disconnecting it from the car while charging will give it the best chance of rejuvinating to full strength.
4) Do not skimp on battery quality, it will hurt you in the end. A good quality battery (Bosch Silver, Varta, OPC) will always outlast a £30 one from the market, even if they have the same 'rating' (eg 80Ah).
5) Trickle charging is a great way to keep batteries alive if you dont drive that often. The CTEK 3600 is a good option, there are other brands as well (search for CTEK on the forum and other suggestions will come up). If you find the lead on the CTEK isnt long enough to reach your battery, go to Maplin and buy some more wire and connectors for £5, and get the soldering iron out.
6) In a factory spec.996 I believe the cigarette lighter is not always live (it is dead once ignition turned off, so wont deliver current to the battery). So before plugging the trickle charger into it, get a Porsche techy to make it live (1hr labour max) or connect the trickle charger direct to the terminals using the plugs supplied with a CTEK. To check if its live, plug in your SatNav or road angel, get out of the car and lock up. If it stays on...
7) If you park in the street, so cant trickle charge from the mains, there are solar panels that are supposed to trickle charge. Won't be as powerful as a mains trickle charger, but if its your only option...
8 ) The standard drain on a car when 'sleeping' should be in the region of 20-80mA (ignition turned off, locked up and left for 90mins). Faulty Trackers (shorting or their internal battery flat) or other non standard electronics left on will obviously increase this. You cant test this, its need to be a garage with decent electronics diagnostics. If you're interested in how its done, PM me.
9) The car 'goes to sleep' after 4 days of no action. Various systems shut down, including the remote alarm facility. Top tip for unlocking easily: Unlock using the key in the door. Immediately lock it using keyfob remote, then unlock it using keyfob remote. Much easier than unlocking using key and quickly having to jump in car and put key in ignition and turn.
10) If you need to jump start, you need to connect the jump leads to the actual engine (-ve) and a terminal located in the engine bay (+ve). This is shown clearly in your manual. Dont connect jump leads to your battery in the front boot.
11) If completely dead, you wont be able to access your front boot as the alarm keeps the manual bonnet-pull locked. Apparently there is a terminal on the fuse board (think its a 30A fuse) to connect a remote battery to which will let you open the front cover (earthing it elsewhere I guess, having never done it myself)