Check engine code P0125 and P1155
Thread Starter
Driver
Joined: Nov 2002
Posts: 114
Likes: 1
From: IL
P0125 Insufficient coolant temperature for close loop fuel control
P1155 Air/fuel ratio sensor heater (bank 1 sensor 1)
I think P0125 is related to P1155.
P0125 check coolant level, thermostat stuck, faulty coolant temperature sensor
P1155 Air/fuel ratio sensor heater (bank 1 sensor 1)
I think P0125 is related to P1155.
P0125 check coolant level, thermostat stuck, faulty coolant temperature sensor
CL Community Team
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From: Miami, Florida
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Thread Starter
Driver
Joined: Nov 2002
Posts: 114
Likes: 1
From: IL
I read the MIL again before replacing the air fuel ratio sensor, the code are P0125, P1155, P1153, P1155. So I bought the air fuel ratio sensor at Toyota dealer and replace the old one, reset the MIL. About, 50 miles now, check engine light didn't show up.
Pole Position
Joined: Mar 2007
Posts: 362
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From: Moscow, Russia
Driver School Candidate
Joined: Mar 2016
Posts: 35
Likes: 1
From: puerto rico
Hello RX300 people! Does anyone knows what this constant P0125 and P1155 combo on CEL means? I've changed EVERY sensor there is (A/F DENSO), even changed thermostat with timing belt, -all parts genuine Toyota- so the P1155 really annoys me,not to mention the 0125.. geez... Also, every valve has been cleaned, properly adjust, maintained or whatever there is and STILL i get these codes. 
Something I notice is that when in a red light, the RPM get a little bit low and the vehicle seems to be loosing power so I have to put it on N and accelerate a bit... ??????
Might be something related to a throttle problem? Or these are totally different problems and are not related? I would appreciate any feedback, I am totally blocked but I sure want to fix this! Thanks for reading!
Something I notice is that when in a red light, the RPM get a little bit low and the vehicle seems to be loosing power so I have to put it on N and accelerate a bit... ??????
Might be something related to a throttle problem? Or these are totally different problems and are not related? I would appreciate any feedback, I am totally blocked but I sure want to fix this! Thanks for reading!
Driver School Candidate
Joined: Mar 2016
Posts: 35
Likes: 1
From: puerto rico
I just made this post:
https://www.clublexus.com/forums/sho...d.php?t=282920
https://www.clublexus.com/forums/sho...d.php?t=282920
Instructor
Joined: Jan 2006
Posts: 1,016
Likes: 22
From: Virginia
Did you change all three sensors (2 upstream, 1 downstream)? In my experience, if you change the correct upstream sensor (either the one by the radiator, or by the firewall) the P0125 will go away.
Driver School Candidate
Joined: Mar 2016
Posts: 35
Likes: 1
From: puerto rico
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