Changing the Main 12V Battery

[Restyle]

Ive noticed during the recent cold spell that my 2004 MCS is taking slightly longer to start from turnover, which is usually the first sign that the battery is on its way out.
Ok, No Problem, So I`ll get a new battery fitted, but what I need to know is :-
...Will the {OEM} cd/radio need recoding due to its power being temporarilly cut off, or do I have say a 10 minute window in which to change it without activating any resets ?

While we`re on the subject, I`d like to hear if anyone has had any problems when changing the battery, either to a different spec than OEM, or with anything else that occured when changing it.

{BTW - I`m an Auto Electrician but dont normally deal with normal road car electrics}

[Fevs]

i removed mine befor and from what i remember i didnt need to recode anything i had to reset all the channels in the radio but taht was it

(dont hold me to that mind )

[Scrogg]

When I was working for MINI we had to jump-start plenty that had gone flat, and never had to enter a code.

I don't see how disconnecting the battery would be any different.

[Restyle]

Quote: Originally Posted by Scrogg (original)

When I was working for MINI we had to jump-start plenty that had gone flat, and never had to enter a code.
I don't see how disconnecting the battery would be any different.

Although a battery is usually considered flat when it no longer has the power to turn an engine, it may still be providing the radio unit with enough charge to keep its code "alive".
The point of radio coding was to deter theft by requiring the original manufactureres code to be entered if ever power was completely cut for a certain duration.

One way around this possible problem when changing the battery is to hook up a seperate 12v supply via the cigar socket while main battery is disconnected, but I`m not sure if this step is neccessary on the MINI ?

[Scrogg]

Good point, I hadn't thought of that (I'm a bit of a dunce when it comes to the technical stuff ) but I've never seen a radio code be supplied with a MINI (unlike most other manufacturers) and I never had a customer come in asking for one, so I guess you'll be O.K.

[M111 CGC]

I've unplugged the radio from the wiring loom many times to fit Icelink etc and never had a problem.

If they are like recent VW head units then they are hard coded to the vehicle. i.e. you don't need to do anything if reconnecting the head unit to the same car, but at the same time I've never seen anyone advertising second hand Mini head units 'with code' so I don't think the Mini head units even have a code anyway. Bear in mind that the head unit is specific to Mini and not much use to any other type of car so the theft value is much less than a generic head unit.

Chris

[cristo]

Mine zeroed the clock and the trip odometer when I changed the battery, but the
radio (including preset stations) wasn't affected.

[Randall Raines]

No code is needed for the OEM cassettes or CDs, as long as they are fitted into any MINI (this applies to 1st Gen, not sure about 2nd Gen), you do get supplied a code card when the car is new, for the stereo and although it has a code number on it you don't need to enter it on re-fitting or re-connection of the battery, I think it's just for in-case the unit is stolen ie. you have the serial number and model number .

The stereo head units actually get a signal from the Body Control Unit and once it has got the signal it works, the only time I saw one of the units freeze out and say safe or something on it was when someone changed from a cassette to a CD and didn't wire the signal wire up .

If it doesn't actually work the 1st time on re-connection, dis-connect the battery again & re-connect it and it should be OK .

just before dis-connection of your battery open your doors slightly just so the windows drop a little, as once you've dis-connected the battery the drop feature wont work and I have known people to break the plastic screen trims or even the door glass slamming the doors to try and shut them (the downside is if you have to leave the car outside the door windows may not seal as good as they should, while charging the battery, no probs if you have a garage ).
On re-connection of the battery always remember to reset your windows or they will get confused, (wind them down a little and then send them all the way up and then they will be reset .

Everything else should work OK, you may need to set your clock .

[Restyle]

Quote: Originally Posted by Randall Raines (original)

....just before dis-connection of your battery open your doors slightly just so the windows drop a little, as once you've dis-connected the battery the drop feature wont work ....

I`d forgotton about that characteristic ... Thanks

[Aberdeen Al]

Quote: Originally Posted by Restyle (original)

I`d forgotton about that characteristic ... Thanks

Aye and don't do what I did when I disconnected the battery......................I slammed the boot closed....................doh! Couldn't get it open as had no power to do so had to remove the parcel shelf the wrong way and then lower the seats to access the battery for re-connection.............................ho ho ho - won't do it again though

[Restyle]

Quote: Originally Posted by Aberdeen Al (original)

Aye and don't do what I did when I disconnected the battery - I slammed the boot closed doh! Couldn't get it open as had no power to do so

Another Gem worthy of Note

[Randall Raines]

Quote: Originally Posted by Aberdeen Al (original)

Aye and don't do what I did when I disconnected the battery......................I slammed the boot closed....................doh! Couldn't get it open as had no power to do so had to remove the parcel shelf the wrong way and then lower the seats to access the battery for re-connection.............................ho ho ho - won't do it again though

Some MINIs have the boot / tailgate release pull under the base of the rear seat , it was optional on the earlier MINIs but I think most of the later MINIs are fitted with it as standard (give base of your rear seat a hard tug up-wards at one of the front corners to release it, and the pull if it is fitted, is in the middle ) .

"Aberdeen Al" your MINI may or may not have this feature as it was about the time of the change, if you still have your MINI that is in your profile .

"Restyle" yours should have this feature if your MINI is the same as in your profile .

[Restyle]

A funny thing happened to me today when I went to start my car ....
It wouldnt even turn over, just the dreaded click - click - click from the solenoid

It wasnt as if I didnt know it was on its way out, but I suppose its just typical to fail on a day when no battery shops in the country are open - Boxing Day
{I dont count the overpriced Halfords who dont even include batteries on their website nowadays as they`re probably ashamed of their own prices}

I did a few checks, with standard fluke, current drain meter & battery charger, which confirmed my thoughts that it was no longer able to accept or store charge.

A couple of strange things happened as I was removing the battery - The Drivers side window dropped by an inch - which I had to tape up, & I carelessly went & slammed the boot !!
I know - You feckin warned me

Found a recent Car Battery Test in Auto Express that gives very interesting reading

I`ll see if I can source a good replacement tomorrow.

Usefull Battery Snippet of the Day
Stamped on the top of the -ve terminal is the date code of manufacture of the MINI OEM battery
Mine reads :-
32
04

= Week 32 {Early August} of 2004

[Randall Raines]

Quote: Originally Posted by Restyle (original)

A funny thing happened to me today when I went to start my car ....
It wouldnt even turn over, just the dreaded click - click - click from the solenoid

.

Quote: Originally Posted by Restyle (original)

It wasnt as if I didnt know it was on its way out, but I suppose its just typical to fail on a day when no battery shops in the country are open - Boxing Day
{I dont count the overpriced Halfords who dont even include batteries on their website nowadays as they`re probably ashamed of their own prices}

Typical!, but if you were getting the signs, you should have done something about it before it went! , prevention is always better than the cure .

Quote: Originally Posted by Restyle (original)

A couple of strange things happened as I was removing the battery - The Drivers side window dropped by an inch - which I had to tape up, & I carelessly went & slammed the boot !!
I know - You feckin warned me

This is just the Body Control Unit getting confused (just reset the windows on re-fitting), did you not find the boot / tailgate release under the rear seat? (you should have it on your model ) .

[Restyle]

After a lot of ringing around, I eventually found a suitable {Branded} heavy duty replacement for the MINIs original 55Ah {Amp-Hour } & 480 CC {Cold Cranking Amps}, for a Bosch 60Ah - 540 CC equivalent.
I tried to hunt down one of those Exide X-Tra + batteries that came top in the AE survey linked above, but unfortunately couldnt find any suppliers in my area.
The cheapest battery I was offered was an unbranded 55Ah for £46, but I decided on the Bosch Silver for £78 inc with its superior technology & 4 year guarantee.

The type of battery classification prevalent in the UK is a 3 digit code that specifies the physical `L-W-H` dimensions & also the type & orientation of the terminals.
The MINI`s code seems to be `075` for all models 2001-2007 , where L= 230 / W= 170 / H = 190mm approx {Although I`m Not sure on the Diesel Varients which might demand a higher capacity Ah rating }
Seems like there is a new type of coding for car batteries as witnessed on the Bosch, strangely called `The European Tyre Number - ETN` details of which can be seen in the pic below.

Anyway, after releasing the hatch by pulling the concealed tailgate release as described above, I fitted the new battery in place, remembering to reattach the original vent tube.
No problems with radio coding resets or anything else occured, & thankfully it started 1st time.