JayGS4

iTrader: (1)

Last week, I've had the battery replaced due to the infamous 'battery light' when coming to a stop and all radio/nav shutting down until you begin to put load and accelerate the car. Local car parts shop tested battery and machine read out voltage below avg 12.5 - 12.8 range. After new battery same issue, and mechanic decided to replace the alternator with a new unit. Everything is good up until yesterday (1 week from replacement) when I had the heat and rear defroster on high.

Took it to the local auto parts shop to have it tested again. Machine read out mentions the voltage regulator has gone bad. Thing is the voltage regulator is part of the alternator and they don't sell the part separately.

Any ideas what is going on? This is a new alternator with a new voltage regulator so everythng should be fine I would assume. Any other areas I can look into/recommend when I take my car to the mechanic shop? Specific wiring or connectors? Please advise! I've searched this topic which is why Ive replaced the alternator and battery already, but please share any additional thoughts or tips you have!

Thanks,
Jay

Mr Jokster

iTrader: (8)

How bout the starter?

VIP161

iTrader: (3)

I'm having a similar issue on my 98 GS300. When the car idles and the engine fans turn on, the radio shuts off. When I'm coming up to a stop light and apply the brakes firmly, the radio shuts off. When I roll the windows down or hit the turn signal, the radio shuts off. I'm still trying to figure it out.

MasterKwan

Unless it's a brand new Lexus alternator, I'd assume you just got a bad replacement alternator. Remans are basically cleaning jobs. All the stuff on the reman boxes about what they replace is lies. They just replace what needs replacing to make it work, clean it, then put it into a box.

27700A 2770050030 REGULATOR ASSEMBLY, GENERATOR. REGULATOR ASSY, GENE; 12V 70A,80A,100A 4000CC 32-VALVE DOHC EFI, 3UZFE; UZS16# $146.47 2770050030

Looks like you can buy the voltage regulator to me.

27020 270605024084 ALTERNATOR ASSEMBLY. ALTERNATOR ASSY, W/R; 12V 100A
$260.48 270605024084

I'd probably buy a new one. I'd be looking at the battery and alternator wires as well as the grounds too.

aneidiaz

OEM is the way to go on these things. In my mind, NEVER replace a key component in the engine to a 430 with an "AutoZone"part.. These cars are too high end to be risking that kind of failure. I know not everybody got that money but for a mere $100 more or less, your better off paying for OEM quality my friend. I hope your issues have been resolved!

repugnante

I always have and always will go OEM when it comes to alternators. I never mess around with that part. I don't care who sees it differently

RyanV

iTrader: (9)

Need to look at the negative battery cable. High resistance in an older cable causes this kind of stuff to happen.

There's a sticky thread in the SC section I believe where Lexus Doctor or whatever his name is talks about this and having to replace negative cable after cable when he was a tech at the dealership.

I've replaced a couple negative cables on older Toyotas of mine and it really can make a difference in how the car runs overall.

ttaylor993

Just to give an amen to what MasterKwan said about a bad replacement alternator. I don't know where Jay got his parts. I do a lot of shopping at Autozone. On more than one occasion I have gotten a starter or alternator from them that was bad or went bad in a short period of time. I agree with everyone else. When it comes to these type parts OEM is the only way to go.

RyanV

iTrader: (9)

I used to work in the Lexus parts dept- they are all pretty much remanufactured parts now. So, if you buy a Nippondenso alternator at say rockauto.. it's essentially the same as going to lexus and paying more money.

Example below...both of these are remanned and use Nipondenso parts

DENSO Part # 2100519 Reman

BECK/ARNLEY Part # 1861117 Remanufactured
AMP 100; PULLEY 6S; OE MFR: Nippondenso; VOLT 12; ROT CW; CLK 12:15; Internal Regulator (Only 2 Remaining)

aneidiaz

I completely agree with you bro! It's not like a Honda Civic where the alternator can be taken out easily. These cars are more complex and taking out an alternator is much more complicated. So if your gonna do it once abd TRULY ONCE your best bet is OEM on that. Also starters or any engine component to me. Honestly speaking.

aneidiaz

Are you sure bro? I've ordered countless parts off sewellparts and I've never received a remanufactured part. I hope this is not the case. I am confident on Toyota quality. I've yet to receive a bad part from them. But I take your comment into consideration. You never know what you'll get these days. Everytime I've went to AutoZone for ANY of my cars %85 of the time, the parts have been DEFECTIVE or completely BAD. On the contrary, I've had good experiences with Advance Auto Parts. Never had a problem with them. I think AutoZone carries the bottom of the barrel so to speak. I hope sewellparts is only carrying OEM Toyota/Lexus in BRAND NEW condition. I haven't seen otherwise.

SC4Paulo

iTrader: (2)

An alternator isn't too bad for our cars, but about the remanufactured alter stores yes, I'd veer away from autozone remans, when it comes to your alternator you might as well buy new for another 100-200k miles. the starter can be remanufactured by yourself for under $100 with genuine Toyota parts, and the starter on the other hand is a bit tougher to get too,

RyanV

iTrader: (9)

You wouldn't know if a part you bought at sewell was remanufactured. Did you know that stock Toyota 'exedy' 'aisin' clutch kits are remanufactured a lot of the time? Yes they will charge you a core and will take the old one back to be remanufactured so they can sell it to someone else.

Lexus parts are Toyota parts and alternators are usually remanufactured. You may possibly get a new one, but it really doesn't matter if its new or remanufactured if it's a Denso alternator.

JayGS4

iTrader: (1)

UPDATE: I've gone through 2 pepboys alternators. One of which my mechanic installed for me but as mentioned I still had the accessories shut off on me. So long story short, Pepboys agreed to install a new alternator free of charge. Everything went well on the second Pepboys alternator (performance wise- no NAV/radio shut off or battery light), but there was a loud whining/hissing noise at idle and when revving. Brought this issue up to the service & parts manager and mentioned these alternators seem to be defective as I've gone through two already.

Ended up buying an OEM Toyota re-manufactured unit from Sewell (to clarify, there was a sticker on the alternator mentioning OEM Remanufactured) for about $245 which came out cheaper than the Pepboys 'Prostart" alternator which I originally bought for $285. Pepboys swapped it out free of charge and refunded me. I have not had any issues since and everything works well.

I would have gone with the OEM part from the beginning but ordering from Sewell would take about a week when my local pepboys had them in stock. But in the future, I am only going the OEM route from now on. The rebuilt units at the auto parts stores are a hit or miss and a huge inconvenience.

tiger4life

iTrader: (16)

Meh.... my car was getting harder to start even though the battery was a few months old. I figured the original alt was going bad after 216k miles and 15 years. Got VSC ligths and sluggish performance this week and then the red battery light came on. Installed an Autozone alt ($124+tax) today and everything is back to normal. I have a gs300 so the job wasn't too bad. If I had a v8 I probably would've thought about the decision harder. Also Autozone is like a 1/4 mile from me so it was convenient.