2000 lexus gs400. can I test the TPS without removing it?? had codes p0120 p0121 and P1128, any other ideas would be helpful. How do I test TPS? thanks

 

You need a scantool, which most garages should have. It should be at a constant 14volts i believe, if not then 15 volts.. you can test it by taking off your engine cover, and then turning the acceleration cable. If it moves with no resistance, you're good, however, if it feels loose and very sluggish, you need to change your TPS. I just changed mine for $10... plus tolls lol

 

now I may be mistaken but it sounds like you are talking about the throttle pedal position sensor which from my understanding is different from a throttle postion sensor??? You are referring to the piece that has the cable attached to it?? I thought the throttle position sensor was on the opposite side of the throttle body underneath a few hoses??? When you say scantool are you referring to a multimeter? 14-15 volts, there are multiple pins which should I use and what setting should I have on the multimeter? Can't I just measure the resistance of the sensor itself. Any feedback would be appreciated.

 

TPS How to test

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

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

Here is how to test for GS430

 

correct for 3UZ-FE, but 2000 GS400=1UZ-FE