Bought an old BMW M3, filled with regret...
- Thread starter mrk
- Start date
Ah nice. I think I’m gonna have a dead battery. By time I get to my car it will be 2months sat and Christmas it was giving me discharge warnings after I left doors open to hoover it.
AGM too as it’s a stop start and has the Battery management system.
AGM too as it’s a stop start and has the Battery management system.
I think in hindsight the best option would have been to just drive once a week. Even if I went to a bigger Tesco for the weekly shop at least I'd have more chance of finding essential items in stock rather than walking to the local, queueing for ages and finding zero packs of surface wipes or hand wash on the shelves. Plus my battery won't drop off the charts and I'd get to drive 
I had to put a new battery in my E92 M3, it was £208 for the correct battery (cheapest I could find!) from a BMW dealer and they coded it in free.
CTEK arrived today so am charging it in the conditioning mode. I've never used a CTEK before but at stage 4 it's ready to use at 80% charged. I will let all 8 stages run as the stages after 4 are full charge and testing and conditioning so if it fails I know the battery is in need of replacing so I can just swap in the new battery when it arrives next week instead of returning that to ECP. This morning the battery was completely dead and would not even turn on the interior boot lights when opening the boot. So within a day it's gone from really low to flat.
Lighter socket means leaving a window slightly open overnight whilst charging which is a no go on the driveway. The eyelet connector that attaches to the battery terminals means the plug end can stay in the boot and I can close the boot fully whilst it trickles over night securely so have opted to use that method!
This charge is still on stage 2 and could take up to 8 hours to complete just that. If the cells inside are broken then it will likely fail at 5 or charge fully and the car still won't start because too many cells are broken. It's not all a home run just yet
This charge is still on stage 2 and could take up to 8 hours to complete just that. If the cells inside are broken then it will likely fail at 5 or charge fully and the car still won't start because too many cells are broken. It's not all a home run just yet
Lighter socket means leaving a window slightly open overnight whilst charging which is a no go on the driveway. The eyelet connector that attaches to the battery terminals means the plug end can stay in the boot and I can close the boot fully whilst it trickles over night securely so have opted to use that method!
This charge is still on stage 2 and could take up to 8 hours to complete just that. If the cells inside are broken then it will likely fail at 5 or charge fully and the car still won't start because too many cells are broken. It's not all a home run just yet
Why the window, just close the door on the cable it is normally okay. However the eyelet option looks to be a good solution for you also. Stage 2 is desulphurisation I think, it can take a while on an older battery, stage 3 is the pain, it took 20 hours to get my DB9 battery back after I was very silly and left it in the garage for a long time without doing anything.
The gap is quite thin between side of car panel and door, don't want to dent the cable at all plus I'd rather not have a cable dangling out the side of the car as the shed is directly behind which saves me over 2 metres of cable length too.
Yes makes sense in that case. Luckily the DB9 has a dedicated cigarette port for trickle chargers in the boot it really is convenient, I just have to remember to trickle it every few weeks. They really are superb bits of kit and probably already paid for it self saving one of my batteries.
It will also be usable on other cars too of course so a solid investment really at such a low cost.
As my usual luck would have it, just spotted the new battery for even cheaper: https://www.tayna.co.uk/car-batteries/bosch/s5010/
Oh well, another site to add to the car parts bookmark folder lol.
As my usual luck would have it, just spotted the new battery for even cheaper: https://www.tayna.co.uk/car-batteries/bosch/s5010/
Oh well, another site to add to the car parts bookmark folder lol.
That does require the cigarette lighter socket to remain active when the ignition is switched off. Unfortunately on an Elise it switches off with the ignition.
It's a great bit of kit to have
CTEK arrived today so am charging it in the conditioning mode. I've never used a CTEK before but at stage 4 it's ready to use at 80% charged. I will let all 8 stages run as the stages after 4 are full charge and testing and conditioning so if it fails I know the battery is in need of replacing so I can just swap in the new battery when it arrives next week instead of returning that to ECP. This morning the battery was completely dead and would not even turn on the interior boot lights when opening the boot. So within a day it's gone from really low to flat.
Still charging on stage 4 as of this afternoon! Disconnected it at one point as was concerned about a faint bubbling sound coming from it having never charged a battery out of the car before so it's back on again. I soon realised it was just the electrolysis in action lol.
The new battery got delivered by ECP too so I'm all covered. Hoping the old one gets to stage 8 by tomorrow morning so I can put it back in and get some work done on the car.
Edit*
It's done! Gonna get up at at he crack of daylight and get this mother back into the car.
And then look at neatly wiring up the trickle charge cabling.
The new battery got delivered by ECP too so I'm all covered. Hoping the old one gets to stage 8 by tomorrow morning so I can put it back in and get some work done on the car.
Edit*
It's done! Gonna get up at at he crack of daylight and get this mother back into the car.
And then look at neatly wiring up the trickle charge cabling.
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Amazon lol. Although it seems to have gone up in price: https://www.amazon.co.uk/gp/product/B00FC42HAA/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1