I want to change my car battery(saxo) with out loosing the power to radio etc. Ive heard that you can wire a battery into the cigar lighter socket while you swap it and the power wont be lost.
Is this correct or is there another way?
The message from "Rob Kirk" contains these words:
Yes, you can get little dongles which plug into the lighter socket to maintain power while the battery's out. Trouble is that some lighters are only on when the ignition's on and that's too much load for the tiddly 9v PP3 battery in the dongle.
You could always just connect a set of jumpleads to the battery terminals.
A PP3 or similar wired to the cigar lighter (if it's permanently live) will keep the radio memory going, but you need to make sure no other load
- like interior lights, etc, comes on as it will kill it. But there's no reason you can't do the same with a second car battery. However, you'll have to be careful not to short the main battery leads etc as you change it as they too will remain live.
or more correctly the leads .With a battery on the other end I presume you meant to say .:-) Stuart
The message from Stuart contains these words:
Well, yes, that too.
Not recommended....but I still do it !!!
Leave the car running when changing the battery... Hear the horror stories.... but have been doing it for 25 years... on new cars even and never had a problem.
JK
So long as you leave some load on, rear window demisters good, the only way it goes wrong is if you short the leads out.
The lighter socket should be permanently live, assuming that PSA wire Citroens in the same manner as Peugeots. /john
Hi JK,
You have been extremely lucky because modern alternators are three phase and produce large AC sine waves without the battery connected to act as an electrolytic capacitor to filter the voltage. This large sine wave can easily destroy your emission computer and other electrical and especally electronic accessories that are on in the vehicle.
Disconnecting a starting battery while the engine is running or reversing the battery leads can be a very expensive mistake.
Kindest regards,
BiLL.......
Well designed electronics on a car will have overvoltage protection. The engine ECU usually has a regulated 5 volt supply, and the regulator will cope with some 40 volts. Of course, if you revved the engine silly with no battery you might well wreck things, but the possibility of a battery connection coming loose in service *should* be catered for.
Yes - my Berlingo van has a permanent feed to the cig lighter.
Stuart Sharp
Out of interest ....... What is the authorised dealer's correct procedure for changing a battery on a newer car ?
Look up Radio Code, disconnect old battery, remove, fit new one.
Is affecting radio code only problem then ? I have a 2 year old Avensis . as far as I know there isn't a radio code ..... radio/cd/ sat nav. integral console. Isn't there any issue with ECU ?
Not on anything I've ever seen. YMMV but I the only reason it's a problem for radios is to make it harder to resell them when they're nicked
First, open your wallet and remove a large amount of money...
If the emission computer is reset, then it will have to "relearn' its settings. To avoid problems with emissions computers, security systems, radio codes and station presets, a second 12-volt battery can be connected in parallel while the first battery is being replaced. Please see Section 8 in the Car and Deep Battery FAQ on
Kindest regards,
BiLL......
What's an 'emission computer'?
A computer used to control the emissions from a combustion engine.
Kindest regards,
BiLL.....
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