Memory Savers - Any good ?

[alcutler]

Hi, Just about to change the thermostat on my 2004 1.9 cdti and read that I have to remove the battery and box in order to gain access - this obviously affects several electrical things ie stereo, windows, Ecu, etc and have thought of investing in a memory saver that plugs into the cigarette lighter socket and feeds in 12 volts to keep the memories going, while the battery is removed.
Just wondering if anyone has used one of these or should I just connect another battery to the leads to keep the memories going!

[lee gsi]

They do work but remember the ignition needs to be on so the fag lighter socket is live first.

[plasma]

eek, I'd never like to back power 12v through the ciggy lighter socket.....

[keefy*2010]

eek, I'd never like to back power 12v through the ciggy lighter socket.....

Halfraud's do that when they change battery.

[John LE]

Halfraud's do that when they change battery.

So thats another reason not to trust halfords

[alcutler]

eek, I'd never like to back power 12v through the ciggy lighter socket.....

The voltage going back through the lighter socket only has to be a low amperage to keep the memory going - in fact you can put a 9 volt battery in the device that is sufficient to do the job if you do not want to be bothered with using another battery - Now those leads you can buy to jumpstart your car via the cigarette lighter - that is another matter!

[alcutler]

They do work but remember the ignition needs to be on so the fag lighter socket is live first.

Thanks Lee - I found that out this morning - I was hoping the lighter would work on the accesory key setting but it doesn't which means the ignition has to be left on while I do the job - which I wouldn't do. There is another outlet in the cargo area which seems to be live all the time so I will probably use that.

[alcutler]

So thats another reason not to trust halfords

I suppose they are fed up of losing stereo codes for customers!

[Das]

I suppose they are fed up of losing stereo codes for customers!

Its not only that, you can cause serious damage to some cars by not putting a 12v feed to some cars when changing the battery, Merc's are notorious for this and damage can run into hundreds of pounds apparently.

[Grumpy1954]

I had a neighbour wanted to change a dodgy battery without losing codes while I had the classic cars, my solution was connect the new battery to the connections with jump leads before disconnecting old battery, then there's no loss of power, provided you're careful not to dislodge the jump leads before you get the connectors on new battery terminals.