[Dukat]

Originally Posted by X3buyerScotland

Some say a team of scientists are quietly studying how Lotus replies with such detail so fast. They were tipped off when it was noted that he could get a beer out if the fridge so fast he was gone before the fridge light triggered, defeating E=mc2

Perhaps Lotus is the Stigg?

[Lotus7]

Originally Posted by X3buyerScotland

Some say a team of scientists are quietly studying how Lotus replies with such detail so fast. They were tipped off when it was noted that he could get a beer out if the fridge so fast he was gone before the fridge light triggered, defeating E=mc2

Don't count out Einstein yet. I'm currently working on solving the LHC (Cern) to Gran Sasso -60 nanosecond neutrino arrival time error.

I'm betting on E=MC2 and probably somebody at CERN with a rounding error in his/her $2 Chinese calculator!

[Lotus7]

Originally Posted by X3buyerScotland

Some say a team of scientists are quietly studying how Lotus replies with such detail so fast. They were tipped off when it was noted that he could get a beer out if the fridge so fast he was gone before the fridge light triggered, defeating E=mc2

Just to be fair, this material has been covered in a somewhat different form in a previous thread (forgot which exact one) so I'm just "re-hashing" stuff I've said before and am probably boring some Forum members to the point of them wishing the X3 used steam instead of "old-fashioned" electrons to start up. One regular member (won't mention his name, but we know who you are) has threatened to put a hand crank on his X3. Sorry!

[sfax]

Originally Posted by Lotus7

Don't count out Einstein yet. I'm currently working on solving the LHC (Cern) to Gran Sasso -60 nanosecond neutrino arrival time error.

I'm betting on E=MC2 and probably somebody at CERN with a rounding error in his/her $2 Chinese calculator!

Haha, surely a rounding error. Computers can't even represent 1/10 exactly, they can only manage an approximation. The ancient Greeks could do better than that

[X5plug-in]

The Ctek comfort connect system looks like a useful idea. Presume the eyelets will fit our terminals? Being a specialist battery, will the Comfort indicator panel system work and is it worth also buying? It would be handy to open the bonnet and see at a glance by coloured lights if you need to top up the battery without needing to connect anything. But would it work with X3?

[Bustofa]

Originally Posted by X3buyerScotland

My dealer reports I have a low battery voltage due to only making short trips with all my gizmos on

I find all of this a bit strange. Surely it would not be beyond the wit of man and BMW to have programmed the system to charge the battery, even with the car under load, if the charge level falls below a certain level. Surely they considered the potential impact of short trips on battery life?
Perhaps something else is amiss here?

[X5plug-in]

Over to Lotus here but I think the point is that as Lotus said the car can be a significant battery consumer sitting still. This means that the only way the car can keep the battery at healthy levels after short trips is the charge it on the go, in effect negating the benefit of BER as this takes fuel. In an ideal world to save as much fuel as possible, every trip would start with a full battery, so any electricity harvested would power car gadgets on the go and when parked etc. My problem is this is not happening so unless I charge up the battery, my BER rarely gets the chance to save me fuel.

[Bustofa]

Yes you're right I think and that is what I thought but using a bit more fuel is surely more convenient than having to separately charge the battery, which costs anyway although not much.

[VikingOne]

Decided to get one of these to be safe, and keep the battery topped up when possible.

http://www.ctekchargers.co.uk/ctek-xs7000.php

[X5plug-in]

Why the 7000 and not the 3600, which is what I understand from AJ is what BMW rebadges in the Uk?

Bustofa- the fear I have is of having a non-starting car at home in the snow which no amount of fuel will start. Worse still, there appears to be no warning system, so an indicator system would let you know. But I agree - BMW should have solved this, maybe via idrive monitoring system that says if you switch off the car by tomorrow it won't start unless you do something.

[VikingOne]

Originally Posted by X3buyerScotland

Why the 7000 and not the 3600, which is what I understand from AJ is what BMW rebadges in the Uk?

Bustofa- the fear I have is of having a non-starting car at home in the snow which no amount of fuel will start. Worse still, there appears to be no warning system, so an indicator system would let you know. But I agree - BMW should have solved this, maybe via idrive monitoring system that says if you switch off the car by tomorrow it won't start unless you do something.

I ordered from Amazon, and had some gift certificates to use, so went for the bigger model. No other reason.

[sfax]

Is there really a problem here though? Mine isn't used for commuting but is often used for very short trips during the week by the wife (1 mile sometimes). No problems with battery in 7 months. Might be good to see charge level for peace of mind but I'm not sure there's a problem unless you don't use the car at all for a month

[VikingOne]

Originally Posted by sfax

Is there really a problem here though? Mine isn't used for commuting but is often used for very short trips during the week by the wife (1 mile sometimes). No problems with battery in 7 months. Might be good to see charge level for peace of mind but I'm not sure there's a problem unless you don't use the car at all for a month

I agree, the problem I have after all this wait, I am now not going to be able to use the car for commuting, and the wife wont drive an automatic (yet!). So wanted to get the charger to ensure the car is in tip top when I do get to use it. I will monitor the battery charge and see how it goes.
Can you see the charge level via iDrive?

[X5plug-in]

Hi Sfax. I have been doing short trips as above and have been warned by dealer things will start shutting down as their computer is showing a flag for low battery. I have had a 3 door central locking failure (which is why it went in) and this has spontaneously resolved itself. Leaving 3 doors unlocked when the car indicates it is locked (but the pins don't fall) is pretty major to me. My dealer seems to be making this link. I am less sure but the voltage was the only error flag.

[Lotus7]

When the X3 is used for "a lot of short trips" the BER mode is not fully invoked. The system tries to keep the battery at between 50% and 80% of full charge. That will give you "something like" 20 or 30 days of leaving the car parked and still allow starting.

Full BER mode (no charging while cruising) does not cut in until the battery is at 80% charge. At that point, the alternator switches to a special "high-charge" mode only when coasting or braking, but virtually no charging when cruising. You can tell if the car is in that mode by monitoring the battery voltage. When the car is in full BER mode the voltage will shoot up to 14.5 or 14.6 when you coast or brake. Once that mode is triggered, long drives can result in the battery dropping down to 60% charge. At that point the car switches back to a pretty conventional charging system where the alternator charges all the time at a moderate rate.

If you do a lot of short drives, you will probably keep the battery charged at something like 70% or 80% of "full" , which is fine and should result in no problems with any of the car's electronics. This summer I've only done a couple of trips of longer than 100 miles in the X3 and do a lot of trips of around 5 or 6 miles and the battery has been running at about 70%.

If you ONLY do a lot of "very short" trips (I'd guess of less than a few miles), or if you have a non-NA vehicle with "Start/Stop" and drive in very slow traffic using that mode a lot, you are going to have a battery that has a potential charge level of 50% . That means a limited storage time. I don't know if the car will switch off the "Start/Stop" function if the battery gets too low, but strongly suspect that BMW would have anticipated this condition and would not let the battery get too low to allow restarts.

I've been using a "smart" B & D 10 Amp charger once a month just to "top up" the battery. The B & D has a "percent charge" meter and the X3 usually reads between 60 and 80% when I start charging. I also monitor the voltage with a plug-in digital voltmeter in the accessory socket. The car never really needs to be charged via the mains charger, but, even though it uses a deep cycle, saturated mat battery (which is much more tolerant of sitting around partially charged than a plain, old wet cell battery), it still will benefit from an occasional full charge. That also forces the car into the full BER mode, which saves a little (3% max) fuel, even in short trip driving.

Do you really need to connect a battery charger? NO, unless you leave the car parked for a week or more at a time, and then don't drive it enough to replace the lost battery charge.
Will using a "smart" battery charger increase the lifetime of your battery and improve your fuel mileage? YES, but only a little (theoretically).

[Lotus7]

Originally Posted by X3buyerScotland

Hi Sfax. I have been doing short trips as above and have been warned by dealer things will start shutting down as their computer is showing a flag for low battery. I have had a 3 door central locking failure (which is why it went in) and this has spontaneously resolved itself. Leaving 3 doors unlocked when the car indicates it is locked (but the pins don't fall) is pretty major to me. My dealer seems to be making this link. I am less sure but the voltage was the only error flag.

It's certainly possible that IF the battery was allowed to get "really low" like less than 10% charge and the voltage sagged to less than 11 volts, the car's preference memory may have been affected during starting, requiring a "reset" or reloading of some programming. It's hard to imagine how this would have happened if the car was being driven at all because the X3 has a very high capacity alternator, and even short-hop driving should result in enough charge to keep everything working.

It seems that some NA X3s are delivered with low batteries (mine was) and it can take a few weeks to bring them up to a reasonable charge with normal driving. I suspect that a X3 delivered in Europe would even have a lower battery charge initially.

[sfax]

Originally Posted by X3buyerScotland

Hi Sfax. I have been doing short trips as above and have been warned by dealer things will start shutting down as their computer is showing a flag for low battery. I have had a 3 door central locking failure (which is why it went in) and this has spontaneously resolved itself. Leaving 3 doors unlocked when the car indicates it is locked (but the pins don't fall) is pretty major to me. My dealer seems to be making this link. I am less sure but the voltage was the only error flag.

I'm always sceptical of dealers conveniently blaming the driver for a fault or making tenuous links. That locking problem is definitely a major issue that needs to be fixed but I doubt it's related to the battery issue.

Without having a voltmeter on hand, you can probably detect if battery charge is low because stop-start won't kick in and maybe (not sure) you won't see the little blue bar for energy regeneration when braking/decelerating

[Bustofa]

Wise words from Lotus again. What would we do without him?

[X5plug-in]

Sfax-stop start is working and the blue bar lighting so I too doubt the connection with the locks. That said, voltage was the only flag. All I can think of is that a very low level effected the lock memory and they de-synched only to resynch later by some automatic correction system. Seems a bit of a long shot.

Lotus- which cigarette lighter volt meter do you use? Wondering if it might be better that the Ctec charge level traffic light device?

[Dukat]

The CTek charger comes with cables you can permanently attach to the battery to use the quick plug. Is it possible to install those cables without disconnecting the battery?

Will unplugging the battery for 20 seconds cause all car settings to be reset or is enough time to swap wires?

[Lotus7]

Originally Posted by Dukat

The CTek charger comes with cables you can permanently attach to the battery to use the quick plug. Is it possible to install those cables without disconnecting the battery?

Will unplugging the battery for 20 seconds cause all car settings to be reset or is enough time to swap wires?

the CTEK adapter cables should be connected under the hood at the red covered terminal and the ground terminal. It can be done with the battery connected, but you obviously have to be very careful not to short the cable going to the terminal with the red snap-over cover.

If you disconnect the battery (which, incidentally is a minor pain in the X3 because of the emergency crash disconnect system attached to the top of the battery), you will loose all presets (mirrors, radio, clock, date, Nave system) and may require a trip to your dealership for a battery initialization. (The car may think the battery has been replaced). Some dealers will charge for this service.

You may also have to re-initialize the seat positioners (not the same as just storing driver preferences - see manual.

I just use the charger’s cable clips, so haven't made any permanent connections (yet).

[Lotus7]

Originally Posted by X3buyerScotland

....

Lotus- which cigarette lighter volt meter do you use? Wondering if it might be better that the Ctec charge level traffic light device?

I use the Vector CEC008. My example reads within less then a tenth of a volt to my lab-grade Fluke reference meter, so I reasonably trust the readings. However, I'd never trust a "$12" DVM without checking it against something of known accuracy first.

I did have to modify the Vector for best results with the X3's accessory socket. As it comes, the Vector "head" can pivot 90degrees. If you plug it into the X3 socket, the "stock" display is upside-down. If you remove one tiny screw from the pivot joint, then move the head past the molded "stop" and then replace the screw, the head will turn in a way that orients the display correctly on the X3's vertical accessory socket.

As supplied, it works fine except the display reads upside-down.