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IS300 TPS & APS E-Throttle Issue

Pete Tee

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So disclaimer I am new to this and be gentle , I am looking to learn and assume I know very little All the help is greatly appreciated. I looked on some prior forums and through the help section but its a bit wordy and confusing. 


So here is the problem I am having Link G4x ecu. I am getting a Code 77 and/or 76. When put the E-throttle to "ON" Mode. 

I have gone through the calibration  of the APS and stored it then the calibration of the TPS and stored it and I am getting the same issue. I noticed something that was weird is that the TPS Main is 44 % on WOT and TPS Sub is 72% at WOT. So I have been scratching my head and wondering if this is normal? 

Also I am slightly confused about where to set the TPS (Sub) 100% value and the same with the APS (Sub) 100% value. Can some one give me a hypothetical of how to set these based on my current map and log.

I have attached 2 logs the first log (8-25-21) is of the TPS/APS calibrated with the E-throttle to "On" mode with the engine off showing the pedal sweep and the values it is producing. 

The second log (8-26-21)is of the car with the TPS / APS Calibrated with the E-throttle set to "Setup" mode as we had the car on the dyno doing a pull to show real time values of it through the range with a load. 



PC Datalog - 2021-08-25 8;43;45 pm(Link1).llgx PC Datalog - 2021-08-26 6;36;47 pm(DynoPull).llgx waynebaseis300(523Whp).pclx

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The dyno run looks like the throttle was working not bad, the PID may need a bit of work later to settle down the little oscilation it has when closing.  But the main problem that is causing the fault is the APS (Sub) 100% setting.  This setting tells the ecu at what percentage of TP main the TP sub "tops out".  Yours looks like it needs to be set to about 70-71%.  You need to manually set this value, change E-throttle mode to Set up and then adjust the APS (Sub) 100% setting.



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Hey Adam,


Just wanted to follow up on this, first and foremost thanks for the quick reply. I was able to make the changes today to the APS and TPS Sub 100% values as you showed in the screenshot using the time plot. I drove the car in various driving conditions and it performed perfect with no " ECU Codes". I appreciate the help again and will post up a new log so that we can work on the PID's once work/life slows down a bit. 

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