Electrical Woes

[Negative Creep]

Car has been running fine until the other morning when I come out and the battery was completely dead - no dash lights or anything. Got it jump started and all was well, no warning lights and the inbuilt voltmeter showed nothing amiss. Came out the next day and the battery was completely flat again so put it on a charger overnight. This is one of those batteries with an indicator and although that shows as not fully charged it was according to the battery charger and it reads normally across the terminals.

 

Connected it back up and we have power again, around 13.98v at idle so all fine. Except that once I put it under loads it goes up to 17v and the dash lights up like a Christmas tree. I don't have a spare battery to try, the only scrappy within walking distance being completely unhelpful and not wanting to sell me one. Possibly the alternator but then why would the battery drain overnight? Any ideas?

[babydriver]

I recon the cells are knacked in the battery and won't hold the charge after so many hours. New one required me thinks, go to highstreet motor factor who will do a free test for you.

 

Good luck

[euphonic]

Most places that sell batteries will test it including halfrauds, sounds like it's knackered to me but watch them test it,i don't trust any one now.I won't mention who ,but one firm said mine was ok when 3 others including the AA said it was knackered.I wonder if it was cause it was still under their warranty and they "sent it away" for a test!!

[mattblack]

By 'load' do you mean when you rev the engine? 17v is too high, sounds like the alternator is overcharging and has cooked the battery (i assume it's a sealed one). Dodgy alternator can drain the battery when standing as well.

[Negative Creep]

Tried another battery on it with the same results. So stopped into my local tame mechanics to confirm what I already knew by that point - the alternator is knackered. Also due to the location of it, the only way to change them is to remove a driveshaft as there's no access from above. Shit.

 

Interestingly though on the way home with all the lights and electrics on it didn't do it. Anyone know of one going cheap?

[Guest]

Tried another battery on it with the same results. So stopped into my local tame mechanics to confirm what I already knew by that point - the alternator is knackered. Also due to the location of it, the only way to change them is to remove a driveshaft as there's no access from above. Shit.

 

Interestingly though on the way home with all the lights and electrics on it didn't do it. Anyone know of one going cheap?

 

Would the one in SL's Camry fit? The SW20s used the two litre Camry engine I think.

[Negative Creep]

There were 2 engine types available in the MR2, mine has the more powerful 3s-ge engine. I think the Camry used the 3s-fe but I could be wrong

[Bren]

You have a knackered regulator - many moons ago you could simply fit a new one to the alternator once it was on the bench, not so sure now if any body sells the parts individually.

[barefoot]

I had a shagged regulator in the VW T2, blew holes in two batteries before I worked it out.

Regulator not replaceable, had to buy new alternator.

 

Fucking bright headlights for a while though!

[Richard]

The Volvo's regulator/ brush pack was replaceable in situ, which was nice.

 

I got it from this guy on eBay. http://stores.ebay.co.uk/Vehicle-Electrics after a fruitless Yellow Pages session.

[Negative Creep]

Started working properly yesterday and it hasn't drained the battery overnight. However I'm guessing the problem will come back sooner rather than later............