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UK Car Repair/Re: battery draining


Hi Chris,
What do think:
The battery on my Sedona drained overnite 2 weeks ago, it wouldnt start, Rac told me I needed a new battery.
Got one fitted at 120 at local garage, then recently I started having the same problems, sluggish on starting. So something was clearly draining it.

So took it to an auto electrician, now its been ascertained, its the alternator, he's managed to source one for 189, but the total is still 310 inc  labor................


Do think its definately the alternator or is my sparky trying to get some xtra cash!

The good news is the guy who fitted the battery is willing to buy the new one back!

if it was a bad alternator it would drain whilst driving, not overnight - think captain slow running out of electricity- unless, exceptionally, the alternator works while driving but drains while sitting.

you need a multimeter to check each circuit for drain (19.99 from argos).

put the -lead to battery- and the +lead on each fuses exposed metal(either side) in turn.
have the meter set to 500ma range (milliamps, to measure CURRENT).

When you find a fuse drawing something over 50ma you have found your faulty circuit. it could be the altrnator but I'm far from convinced.

when you know where the drain is and how much I can help further or you can get onto a garage with the required ammo.

check for things like glovebox/boot/door lights staying on if not willing to buy+dig around with a multimeter.  

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Christian Boyce


Extensive knowledge of cars designed between 1900 and 2000. I have an interest in keeping these early cars on the road - I love the classics and want to keep them around. I'M BACK!. A LOT of reasonably classic cars are going TO SCRAP with no good reason. I want to stop that. If it's cool and you're having trouble with it, just ask. Also I'm looking for a job. I can do bodywork too. Not welding yet. Everything else and more though.


Too much to list............ Honest, I tried.



Elec-Installation (bolton college) Digital and analogue Electronics (Bol Col.) Digital Microprocessor Electronics (Bol Col.) - Pc Inst, Diagnosis/Repair NVQ3 Bury College.

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Man of the match!, 1st place Blackburn indoor karting, 15th overall RallyQuest 2009 (Rally driving).

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