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Dash Lights At Low Revs Is It Alternator?

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all the dash lights come on below 900rpm ( no MIL engine warning light ) rev to 1200rpm and they go off and I can drive like this for weeks and its starts on the turn of the key every time,

Battery charge is 9.5 volts and Battery is new and just ordered new main engine relay which seems to have continuity problems when relay removed ( pins 4 and 5 show continuity ) any one else had this problem its electrical and not my area of expertise all help would be grateful because its costing me a fortune to sort out otherwise the car will have to go

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You say the charge voltage is 9.5v?

If I remember correctly the Battery should be 13.5v when the engine is running and charging correctly if it's as low as 9.5v it sounds like it's not being charged.

Why not run it to one of the auto places that does a free alternator and Battery test to confirm.

I would with the output being so low suspect the diode pack has a phase down.

You haven't in the past had the leaking PS pump problem which can result in alternator failure?

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Hey boys

Are you sure that the dash should occur a problem even if the Battery is showing a low voltage? The reason why, is when i bought my car the first problem i had is the Battery, it was crap to say the least, but the dash board was a capacitor problem?

Mate have does your dashborad ficker at all?


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dash lights dont flicker so I bought a new Battery to eliminate that and the main engine relay and it read 14.5 volts at the Battery but as soon as the revs drop to idle the voltage drops and the warning lights come on and a slight rev and they go off, im thinking its the diode pack but looks a pig to get that alternator out, any tips or is it just get in there and scrape the knuckles.

alternator cost from Toyota is £240 inc vat,

Battery cost £59.99 from Halfords,

main relay cost £18 from Toyota

anyone got a cheap/second hand/rebuilt alternator laying around

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just been taking to the guy who owns CS motors in Stockton and what a nice bloke he is,

he told me exactly what the problem was ( alternator diode ) as was suggested here so im going to bite the bullet and fit a new alternator,

he even told me the easiest way to remove it and its from the top of the engine not from the bottom which I thought but still a fiddly job but worth it because I love that car to bits,

thanks for all your help guys it was much appreciated

oh and just to let you know this guy only does Lexus so an expert on them he is also doing LPG conversions from £850 so worth a look at later

his phone number is 01642 666777 if you need him at any time and his garage is on the TOTAL garage at the rear in oxbridge Stockton on tees

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Glad you got a result and posted it!........theres a few LS being broken up on Ebay, if you want to delay the £200 plus bill......

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Ive decided to go for the new alternator simply because its new and guaranteed so no false economy in the long run,

I was just going to renew the diode pack but knowing my luck the brushes would go soon after lol the alternator is the original one from new so 16 years old and that's not bad for ware and tare by any standard so a big plus for Toyota there,

Ive seen those parts on eBay and its ok if your looking for a major item but thanks for pointing it out to me,

it took me an hour to get the alternator out because I had to remove the power steering pump and a few other things but im quite pleased with that and its given me my confidence back because the v8 can be quite daunting to work on but now ill have a go at anything like the old days

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