Flaked430

Hello everyone! I am a new LS430 owner (2005 Base) and am excited to join this community. I am looking to fix some of the things wrong with my car and could use some help.

1. The courtesy step light on the passenger side and passenger rear does not work. I am assuming it is a wiring issue as I replaced the bulb and tested the housing by trying it on the driver's side and they work just fine. I checked the fuses on the passenger side with a fuse checker and they were all good. I was advised to check the body control module but I have not done so yet.

2. I am getting a voltage reading of 13V from my alternator. I am assuming my alternator is going bad as 13.7V+ is the recommended voltage. How soon do I need to replace my alternator?

3. Other electrical issues include the clock resetting to a random time every time I start the car (I was assuming this was a battery problem but I got the battery checked out and it is 100% charged and working), and the side mirrors going down when I shift to reverse work only 30% of the time.

4. My last issue is the bad MPG I get. I live in Texas and drive some city and some freeway. I get 15-17 mpg. I put either 93 or 89. Is there any way to get better MPG?

I will appreciate any help and I can answer any questions if it helps. Thank you, everyone Finally a proud Lexus Owner.

BigBoomer

Since you have the Engine Warning light and Check VSC you will need to fix those to sort out your gas mileage.
Get a code reader plugged into the ODB2 port and post the codes.

Even though your battery has tested as good, I would still buy and fit a new quality battery.
The LSes are very sensitive to battery/voltage issues.

If your alternator is only producing 13.0V at idle did you test it with someone holding the engine at 2000rpm?
It should be producing between 13.2 and 14.8V at 2000rpm.
Any lower than that and you need a new Alternator, and the sooner the better.
It's quite likely that some of the other issues you have are being caused by low voltage.

Flaked430

I did the alternator test while it was 2500 rpm and it was 13V. I will look to get the alternator replaced soon. Where should I go to get an alternator, my mechanic said he’s had bad luck with AutoZone alternators.

lorenr

iTrader: (1)

Open an account at Rock Auto. You can buy everything you need from them. As long as you are doing this buy the OEM replacements. They will be recommended on Rock Auto's web site. Looks like a remanufactured Denso is about $125.00 exchange. A new AC Delco is a bit more.

Have your mechanic do the work. I'd replace one part at a time.

One trick I use is to get a jar of petroleum jelly. Any time I take an electrical connection apart I clean it carefully with the jelly and put it back together. Has solved a lot of goofy issues.

Loren

Yamae

A 2005 L430 has an alternator which has an additional pin #4. This pin is controlled by the ECU's charging control function. The ECU is checking the status of the battery measuring both the voltage and the current. When ECU judges that the the battery is charged enough, the alternator is forced to reduce the charging current through pin #4 and the voltage-wise, it is 12.8V-13.0V. Some of dealer mechanics even don't know this fact. Some parts shops don't have the checking machine to check those alternators that have the charging control function. You have to be careful for this when you check the alternator.

Flaked430

Oh wow thank you, So you're saying that my alternator could be in fact fine?