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MG MGF Technical - Any problems with Battery Conditioning Charges

I'm considering buying a battery conditioner/charger. I understand that these units can be left connected to the battery for long periods of time without having to disconnect/remove the battery. Does anyone have any experience of these and are there any risks involved with their use, eg potential damage to ECU, etc? I obviously want to avoid expensive mistakes both in terms of buying the unit and also damaging the TF.

Comments appreciated

Bob
R Thompson

Bob,

I have just replaced my 5 year old battery, which was never brilliant at holding its charge.

I've also bought a trickle charger which can apparnetly be connected to the battery in situ. It provides a low current, but cuts out when the battery is fully charged.

I intend to use this when the car is layed up for any length of time.

Sam
Sam Murray

Bob,
I've used an Optimate on my motorcycle (which has an ECU) for a number of years, for months at a time.

I've also used it on my mgtf to charge the battery for about a week. No harm done, however....
It won't charge a flat battery on the F whilst the battery is still connected to the car. I believe that there is a large spike of current demanded by various systems on the car, that will cause the Optimate to think that the battery is beyond recall.
Also, I note that the owners handbook says that that the battery should be disconnected before charging (don't know why)
GrahamH

I got one from Mike Satur in Nov 01 and have been using it ever since.
I had to make a practical everyday permanent live connection for it by fitting it with a cigar lighter plug and wiring the socket into a suitable fuse.
It won't stop battery discharge due to a sticking MEMS standby relay though.
Jon Baker

My Coulombi XS3600 from B&G is connected for 6 months a year whilst the car is laid up for the winter. No problems whatsoever with regular instant starting.
It is wired in under the bonnet using the supplied flylead and push connector.
Smaller chargers designed for motorcycles may prove inadequate.
Early cars had a 'Live' cigar lighter socket so a charger can be connected but later cars have an ignition switched socket which cannot be used.
Geoff F.
G. Farthing

How early were the cars with a "live" cigar lighter? My 96 F has an ignition switched socket, which is a minor irritation, or is there something wrong?
Graham Martin

Bob

I have two trickle chargers. The first was a cheap one from Halfords and it worries me because it never shuts off, even if there is no drain on the battery. So as ever when you've tried to save money I had to buy a 'conditioner' and that works very well. It even has an indicator to show you how much charge the battery has and it does stop the current when the battery is fully charged. The conditioner is available from the following link-

http://www.airflow-uk.com/battery-conditioner.htm

I use the conditioner on my MGF and it doesn't cause any problem with MEMS and the charge light flickers as it replaces the drain from the alarm and clock etc. My wife's Lotus has no such drain on the battery so the conditioner shuts down completely when the battery is charged until the door is opened and the dash light comes on.

Hope that helps

Neil
Neil Stothert

Thanks for the advice. I'll go ahead and take the plunge.

Regarding the 'live' cigar socket (and this might be a daft question), my TF is MY2003. I have a small tyre pressure gauge/compressor that works off the cigar socket. It works without the ignition being 'on'. Does that mean it is permanently 'live'? The unit I'm looking at (CTEK) can be supplied with cigar lighter adaptor for about 5 extra. I will order the adaptor anyway - just wondering if it likely to work.

Bob
R Thompson

Bob,

Sounds like your lighter socket is live at all times. Lucky man!

Sam
Sam Murray

My 2004 TF also has a permanently live lighter socket.
GrahamH

On the older cars ; Locate relay "276" and remove it. Make a short link with 2 "spades" and bridge the relay socket between "30" and "87" . This will give a live circuit at all times at the cigar lighter socket.
Saves the mobile charger,GPS-unit etc. from switching off every time the engine is stopped... / Carl.
Carl

Carl,

I assume that this causes no lasting damage? Also, is the power to the socket cut when the car is started with your configuration?

Regards,

Graham
Graham Martin

this will just wire the socket perm on, but make sure you bridge the right terminals or you'll end up with one of the following:

No power - fuse blows instanty
No power - fuse blows with ignition
No turn off, turning the key doesn't switch off the engine!
Socket power routed thru wrong fuse, cusing burn out of wiring or ignition fuse when using higher current items in the socket.

Of course in each of these cases the socket won't work correctly:
no power
no power
no power
socket comes live with key

so if it doesn't work like yo9u expect then you've stuck the wires in wrong!
Will Munns

Will,

Thanks very much!

Regards,

Graham
Graham Martin

I have three airflow battery conditioners - used on different cars - some almost permanently.

They work as advertised and can restore apparently dead batteries to full working order. I agree the Halfords "trickle" charger is a potential battery killer.
Derrick Rowe

Probably worth noting that if the lighter socket is modified to "always on" then the illumination, if fitted, should be disconnected to avoid excess battery drain.

Sam
Sam Murray

I have an Oxford intelligent charger, it does what it says on the box. I also have a home made one from the 60s which will recover a discharged battery, although this may be of limited use as sulphation will have happened.
I leave the Oxford on all winter the car will crank fine anytime and there is no discernable drop in acid level. I would say get one.
Stan Best

This thread was discussed between 09/03/2006 and 14/03/2006

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