Trac Control And Vsc Light Still Not Off

[ma4220]

Initially the Check engine, VSC, and Trac Control light was on. I went through and replaced the O2 sensor on the rear manifold, checked gas cap, and checked the vacuum hose behind the air box. Now everything should be good, All the lights went off when I reconnected the battery; but shortly after, the VSC and Trac Control light came back on. I have been told I need to hook a scanner up to it and do a step-by-step process to reset the lights. Does anyone know the process I need to go by. Or has anyone else had this problem?

[joe913]

Pull the ECU fuse in the box next to the battery. Leave it out for about 30 seconds. This way you reset your computer without resetting your clock, etc.

On my RX300, I ended up changing the fuel cap even though I tightened the old one until I heard several clicks. My lights went off and have not come back on after several days. I saw a post that suggested putting several wraps of teflon tap under the fuel cap "O" ring to make a tighter fit (you will need to pop the cap from the threaded part). I just replaced the cap.

BTW, the sensor on the rear manifold is an Air Fuel sensor (A/F, B1 S1). Did you use a Lexus, Toyota, or Denso? They work differently than the regular O2 sensor. Not saying this will fix the problem. I'm at the end of my knowledge base. Good luck!

[ma4220]

I changed it with a Denso. I'm pretty sure it's not the gas cap but I will check it again. But I will for sure pull the ECU fuse and see what that does. Thanks for the help!

[mikey00]

There is a known problem with the ECU that after a CEL has been reset and problem corrected the VSC and Trac lights stay on. This is very common on the Highlanders and seems to happen mostly to 2003 RXs. You need to do a zero point calibration. This is very easily done by connecting certain pins on the OBDII connector. I will try and find the procedure for you.

Edit: Here you go. Read the posts and follow the links within:

http://us.lexusownersclub.com/forums/index...p;hl=zero+point