# Voltage regulator or Alternator???



## vin225 (Mar 27, 2006)

Probably a stupid question but my battery light just came on.

Does this mean the alternator and the battery is on it's way out?

Thanks in advance.


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## BlackBlur (Mar 29, 2010)

means your battery aint charging, see what voltage your car throws out when running... should be about 14v if not then its something in the charging system. You can see this value in the AC menus i think


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## vin225 (Mar 27, 2006)

I had to have the RAC out and he said it's the alternator :roll:

I've been reading some archive posts and the voltage regulator seems a common problem. How do i know if it's the regulator or the alternator??


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## nordic (Apr 26, 2010)

Sorry to hear about the problem. Regulator is inside the alternator, a small electronic board with rectifiers and few other components. Alternator itself is more mechanical thingy, it may have bad bearings, pulley, etc, but if it is spinning nicely, it would be the regulator most likely. I think regulator is not sold separately at dealer (correct me if I'm wrong). Need to take to specialists to see the real cause.

Very unlikely, but the battery may be the culprit as well. If it's old, it may be putting an extreme load on alternator dropping the voltage below threshold. Same for the short circuit somewhere.


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## snappy (Apr 29, 2009)

Follow this link helped me out no end! viewtopic.php?f=2&t=142831&start=0

Voltage regulator is cheap and fairly simple to change yourself, compared to doing the alternator.

From what you say, you have exactly the same prob as i had a few weeks ago. changed mine and now back to normal.

The voltage regulator can be exchanged at the dealers along with £38


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## vin225 (Mar 27, 2006)

snappy said:


> Follow this link helped me out no end! viewtopic.php?f=2&t=142831&start=0
> 
> Voltage regulator is cheap and fairly simple to change yourself, compared to doing the alternator.
> 
> ...


I've ordered a new voltage regulator to see if that cures it.

Anyone know how easy it is to change??


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## snappy (Apr 29, 2009)

Yea, did mine few weeks ago. Its fairly easy to replace.
I thought i better remove battery terminal 1st, as i didnt know wether i would get any shocks when messing around with the alternator.

1. Remove cover around dip stick ( if you cant take the 2 screws out that you see from above, undo the 2 that hold it to the pipe from underneath the cover). Be careful of the dip stick pipe at all times as it can break(as a number of guys on here had this go).
2.There are 5 nuts and screws holding the regulator and its cover on to the alternator, remove them all. You WILL have difficulty getting to the philips screw at the very bottom (its a bu**er), I found a flexible screwdriver at B&Q did the job.
3. DONT FORGET TO REMEMBER where each screw and nut go!!
4.I couldnt take the cover out due to one of the pipes being so close to it, but moved it just enough to get the regulator off.
5.Get your new regulator and replace in reverse order.

By the way, a small make-up mirror is useful to see positions of some of the screws. I stole the gf's, sssshhhhhh!

Hope this helps, good luck.


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## vin225 (Mar 27, 2006)

Thanks very much Snappy, i'll give it a go..probably lots of swearing and grazed knuckles :lol:

Cars hey :roll:



snappy said:


> Yea, did mine few weeks ago. Its fairly easy to replace.
> I thought i better remove battery terminal 1st, as i didnt know wether i would get any shocks when messing around with the alternator.
> 
> 1. Remove cover around dip stick ( if you cant take the 2 screws out that you see from above, undo the 2 that hold it to the pipe from underneath the cover). Be careful of the dip stick pipe at all times as it can break(as a number of guys on here had this go).
> ...


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## snappy (Apr 29, 2009)

Yep there will be a bit, but hey when she breathes into life again, the feeling is sooooo sweet!!!


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## vin225 (Mar 27, 2006)

snappy said:


> Yep there will be a bit, but hey when she breathes into life again, the feeling is sooooo sweet!!!


Thanks to all who replied the car is running like a dream again  .


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## big-dave (Feb 14, 2009)

Had my alternator/voltage regulator fail on my 2002 TT in Cornwall. I managed to drive the 200 miles home on 2 fully charged batteries running nothing else electrical. I will get the voltage regulator changed soon but in the mean time I am keeping a fully charged battery as a spare in the boot and avoiding night driving.


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## nordic (Apr 26, 2010)

In that case I would change the motor to an electric one


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