AngelMarie

Hello folks,
Acquired an RX350 several months ago, and have been transferring all my equipment to it. My last car, an 04 Mustang V6, I had to install a higher capacity alternator and Optima Yellow-top just to keep from killing it.

This RX has the full towing package (including hitch), which is supposed to include a beefed up alternator. However, running several DC accessories and a 400watt AC Inverter has my TechStream reporting 13.3-12.9v DC.

Suggestions for a solution? Bigger alternator? Second battery (and-or where to put it)? Probably going to be ordering a Yellow-top soon regardless.

Thanks!

ukrkoz

Can yu get to alternator terminals? Remove them and clean? Before panicking? Question also is, where from is TS reading the voltage? At what point in that circuit? At alternator? At battery?
To fully charge in reasonable times, alternator output must be 14.2 V to 14.5 V as measured right across the battery posts.
https://www.google.com/search?source...30.MbfgWUwSPhA

Lexuswiz

iTrader: (1)

Tow package alternator isn't that much bigger than stock, ~130 amps vs ~100 amps, not sure why Lexus makes it seem like such a big deal. I've put 250 amps alternators on cars with a big three upgrade for a banging sound system, that's a significant upgrade. Toyota/Lexus does have a few HO alternators (160-250 amp) lingering around the internet, you have to look as it's not a great selection compared to American cars. Mechman can also make you a custom one if money is no issue. But, with any HO alternator, you need the big three upgrade otherwise you're bottlenecking the power through the tiny stock wires. You can actually try a big three without a new alternator and see if that makes a difference.

Also, personal take but Optima batteries are past their prime and are mostly just hype now. I've had a few go bad on installs I do and have dropped them completely. If I need an AGM battery, XS Power or Stinger are my choices. Otherwise standard Interstate batteries from Costco have not failed me yet.

AngelMarie

Fair statement, for sure. I don't know where TS is reading its volts. I was reading from the ECT live data fields. Today I only had time to hook up a volt meter to the OBD2 port at this point. I was able to see a consistent 13.9-14.2v @ +/-1800rpm going down the road. At idle it went down to about 13v. I can try and tap at the battery some other time.

AngelMarie

I'm mostly just looking for a deep cycle battery that can take the heavy drain over and over again. On my Mustang I actually had a Brunton solar cell on my rear window just to trickle charge the battery when stopped. It only put out 1-1.5a max but it did the trick.

Thanks for the thoughts on alternators also.. I didn't want to go much higher than what the factory wires can handle at this point. I suppose I could look around for a ~160A unit, but would not go any higher. Heaviest load scenario is that I might go with a 500-600watt inverter, enough to run a couple laptops, a cell booster, and any other accessories on a long trip, plus trailer.