ttran1999

Hi,

Suddenly my 2004 LS430 Check Light Engine, VSC Light and TRAC OFF light came on. I pushed on the TRAC ON/OFF switch but nothing happens. Please help me if you know the answer to this problem. Your time is greatly appreciated.

Thanks,
TTRAN1999

DDLexus

are you having any trouble with the throttle response? If so, probably a Throttle Control ECU. If not, it might be one of the O2 sensors. A connection to the OBD2 port should tell you what the problem is. Autozone or Napa usually have this tool to help diagnose. Of course, the dealer will do this for a fee.

ttran1999

Thanks for the info. I am assuming when you are talking about the "throttle response", you are talking about the response when I push the gas paddle? If so, it does response a little slower than usual. Thanks for your quick reply.

DDLexus

do a search on "limp mode" and you'll be able to see what others (mostly from the GS400/430) forum has encountered with their cars.

StanVanDam

A CEL means a diagnostic trouble code (DTC) is thrown. Get someone with an OBD2 scanner to show you what codes are being thrown. Auto parts stores often will be able to pull the code(s) for you in their parking lot for free. After you have the code(s), you can start troubleshooting.

lex2001

My check engine light and VSC came on after a four hour drive two weeks ago. One of the threads here mentioned that if the gas cap is not on right you may get those errors. The next time I filled the tank the lights disappeared and haven't been back in a week. Fill up and see if it works for you. Otherwise go to an auto parts store and have them pull the codes like posters above said. It's normally free.

m3nv

All the lights are related. Its most likely a O2 sensor or gas cap. Go get the code read at an autozone

IXI187IXI

iTrader: (3)

tighten your gas cap

V8_Fan

x3. Check the gas cap. This happened on my honda (cap wasn't tight, threw the check engine light). Often, you can flip around the O-ring if it's leaking to get more mileage out of it. You should still clear the codes w/ a OBDII tester, then see if it reappears.