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funky charge fault

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funky charge fault

Ok my battery keeps going flat so i fitted a new alternator after testing but one week on and my battery is flat again :banghead:
Ive tested the volts from the back of the alternator and they are 14 but when i test the battery only 12 are going in. Also ive lost the battery light on the dash does anyone know what the fault is. Thanks Mike

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Could be the battery on it's way out - a knackered battery sometimes won't take a charge.  Has the battery gone completly flat and been recharged quite a few times?

1983 VW Golf GX - now sold!

1998 Rover Vitesse Coupe

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Check connections on battery and alternator are clean,inc Main battery earth

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Re: funky charge fault

mk1-mike said

Ok my battery keeps going flat so i fitted a new alternator after testing but one week on and my battery is flat again :banghead:
Ive tested the volts from the back of the alternator and they are 14 but when i test the battery only 12 are going in. Also ive lost the battery light on the dash does anyone know what the fault is. Thanks Mike

have you test both while the car is running ?

as the wires are connected the volts should be the same , there is no reason other then a small earth short for this volt drop.

the volts seem right if you tested the alternator when running and batt when off .

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dude check you're messages  8)

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Thanks guys im looking towards the battery i just wanted to see if anyone else had this fault before.
i tested both the batt and the alt with the engine running thats why i cant understand the volt drop maybe there is some coroded wire somewhere not letting full voltage through. Ill have another look and if i cant find anything ill get a new batt cheers for the help.

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Hmm. This sounds very similar to an issue I had. Drove the car and noticed that the battery voltage was dropping. Did what you did and changed the alternator. Seemed OK, but got from NW London to M4 and battery died again! Changed the battery and drove down the M4 - noticed that the battery was slowly discharging (have voltmeter in car). Got to Wales and nearly flat again!!! Anywat, had a look around and noticed that wire to solenoid had snapped! HAd this repaired and bingo!

This saga is not over though. Car was not used for a while and I noticed that battery was struggling to hold charge. Seemed to be all over the place - voltmeter jumping off the scale!! Went to an an auto electrican and changed the voltage stabiliser in the alternator. Prior to that it had over charged the battery! So, another new battery!

Last bit - promise - and I think this is key! Change the loom from the battery to the alternator. Any good auto electrican can rig one up - has made a HUGE difference - explained why I was getting through batteries - they simply were not getting the juice. I think there is a market out for new looms as the wiring simply degrades in a car 20 years old

Good luck
 :wink:

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Bytor thats great just what i needed as i cant find the fault what you have sugested sounds like the answer. When i was checking the wiring i did notice it looked past its sell by date so ill get a new loom made up.
                        Thanks Mike.

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Cheers for all the help guys it turned to be coroded wire on the starter but full new loom being made in work :lol:
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