frankjames

i have noticed these lights are an issue on a lot of posts (VSC, VSC off, and CEL), has anyone compiled a simple testing procedure for the various sensors. Can't you do a resistance test to see if sensors are working using a multimeter??? EX: Pin A and Pin C= X voltage? Since this is such a common problem this would be extremely helpful. Currently pulling codes p0120,p1121,p1128 thinking it's my tps (throttle position sensor) but I want to know for sure before i spend the money. Any direction would be appreciated.

Debonair

Year? 300/400/430?

frankjames

2000 lexus gs400

Jason T

https://www.clublexus.com/forums/gs-...cel-codes.html

Check your codes via DIAGNOSTIC block in engine bay terminal TC & E1 with a paper clip

Dash lights will all flash count the orange engine light only

http://bahamutcars.free.fr/workshop/...nts/index.html

Repair Manual / DIAGNOSTICS / ENGINE this will take you to engine fault code list

Follow the flow charts to fix

Sound like you have TPS issues (throtle postion sensor)

Check your emissions tag on under side of bonnet / hood if says OBD2 then this will not work you will need to use a scanner

TPS How to test

http://bahamutcars.free.fr/workshop/...nts/index.html

Repair Manual/ELECTRONIC FUEL INJECTION/THROTTLE BODY/ON-VEHICLE INSPECTION

Debonair

Are you sure the GS300 specs you posted above are the same for the OP's GS400?

frankjames

Update- Still idling at about 1200rpm, vsc/vsc off lights illuminated. APPS resistance check good, can here throttle control motor turn on when APPS is moved however am not getting the right resistance from it(throttle control motor, multimeter doesn't move at all when proper connections are made), can't get to the TPS to do resistance check. What are we thinking out there???

Jason T

Here is how to test for GS430

frankjames

actually the first post was accurate for my vehicle-2000 gs400, the last post is for the newer gs430

Jason T

Use http://www.toyo diy.com/ to get part number you need