Power keeps failing

Vehicle maintenance and repair questions in here please for all questions relating to Cars, Vans etc.

Moderator: Moderators

Post Reply
Newly registered Member
Posts: 16
Joined: Mon Oct 30, 2006 11:56 am
Has thanked: 3 times
Been thanked: 1 time

Power keeps failing

Post by RP » Thu Mar 15, 2018 12:16 pm

I lost all power a couple of days ago and the garage say that I need a new alternator fitted, approx cost £400.
I had a new alternator fitted 6/8 months ago because of the same problem.
Could there be another reason for this power loss, every time the garage charges the battery and drive the car around for few hours it looses all power, the battery is only 6 months old.
Thanks for any suggestions.
User avatar
Senior Member
Posts: 24690
Joined: Sat Jan 10, 2009 3:49 pm
Location: hants/dorset border
Has thanked: 1325 times
Been thanked: 3632 times

Re: Power keeps failing

Post by wine~o » Thu Mar 15, 2018 5:14 pm

Assuming the battery and the alternator has been checked by the garage (both should be within manufacturers warranty BTW) then one other possibility is the rectifier... The alternator generates AC voltage and the rectifier (a series of diodes) convert this to DC voltage.
These users thanked the author wine~o for the post:
Rating: 7.14%
Verwood Handyman

Verwood Handyman


If you feel you have benefited from the Free advice given on the Forum, Please consider making a donation to UHM's Nominated charity, read all about it and donate here :

User avatar
Senior Member
Posts: 10338
Joined: Mon Mar 15, 2010 11:49 pm
Location: Oban
Has thanked: 290 times
Been thanked: 1559 times

Re: Power keeps failing

Post by kellys_eye » Thu Mar 15, 2018 5:38 pm

RP wrote:every time the garage charges the battery
If they put the charger leads on in REVERSE then they could cause damage to the alternator - easy to do, difficult to prove.
sent from my laptop using my fingers - because we REALLY need to know where it's come from.....
Senior Member
Posts: 3548
Joined: Sun Jan 31, 2010 9:21 pm
Location: Kent, Land of Apples and PYO
Has thanked: 51 times
Been thanked: 629 times

Re: Power keeps failing

Post by Bob225 » Thu Mar 15, 2018 6:26 pm

If it was done by them its under warrantee but you may have to pay there labour

What car, year and mileage ???
Post Reply

Return to “Vehicle maintenance & Repair”