Hi brothers and sisters of the LexusClub community. My name is Robert Siu, currently working at a local auto repair shop in Brooklyn NY. How is everyone doing today? I hope everyone is having a blessed day.

Anywho, I am currently working on a 2002 ES300 and is having a little difficulty diagnosing this trouble code P1127, which indicates a problem with the ETCS (Electronic Throttle Control System). We replaced the throttle body and is in the process of replacing the computer as well, but need some help in regards to reprogramming the computer since changing the computer will disable the car's ignition capabilities. Much appreciated with anybody having knowledge or any advice regarding to this problem.

Thank you in advance and God bless!!

Sincerely,
Robert Siu

 

If you change the computer, without swapping in a new security system, the car will not start. There is a small metal box, which is wired in separately to the ecu, some distance away, it takes a signal which is generated by the coded key, and receiving ring around the ignition.

There is no way past this. you need to match the ecu, with the decoder, with the key, and barrel.

I doubt the throttle control issue is related to the ecu, it's more likely something else.

The code P1127 seems to relate to a power fault with the Electronic Throttle Control System, it seems to suggest the system is not powered up, or rather is not responding to the ecu to indicate that it's powered up. The fault is therefore unlikely to be the ecu.

http://engine-codes.com/p1127_toyota.html

 

i believe there is a tsb for the throttle body actuator sticking. No start or cranks no start. normally the actuator gets carbon fouled. after replacing disconnect the battery cables and touch them together for 5 min for a hard reset and start the car and let it relearn its idle points.

 

I currently have a p1127 code on a 2002 es300 with 188k miles & I'm looking for possible solutions.

Any help offered would be greatly appreciated.

Thanks in advance