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Discussion Starter · #1 · (Edited)
O2 plug locations

hey guys i just got a IS300 and i have a cell P0051 (among others)

the car does have a megan header

my question is.. are the plugs different for each sensor ?
so would it be possible to plug in B1S1 where B2S2 plugs in i ask becasue that sensor is new

edit i have an answer to this but still need to know below

i have read about the o2sim but i thought was only for the post cat sensor is that true?

if i add an o2 sim for B2S1 i will get a false correct reading but isnt that bad?

i guess i dont understand why a header would cause "heater control circuit low"
 

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yea i have been reading and reading and reading and reading

the code itself is p0051 which is the heater control circuit

im running VERY rich went thorough 3/4 tank 120 miles :(

im also getting misfire codes for 4,5,6 (which now to think of it thats bank 2... interesting)

i did notice that the o2 is really close to the firewall... okay ill check out the wiring all the way back to the ECU and report back

thanks

hello i have searched for an ECM pinout only to come to dead links i have also downloaded the FSM and cant find a diagram

so if anyone has one or knows where i can find a 03 ECM pinout for IS300 or tell me where the 4 wires for the o2 B2S1 wires plug into or even the colors that of the wires once it gets to the ecm that would be great

thanks

okay so after some looking around i have concluded that some one has hard wired in the o2 sensor (thanks jerk) so not im not sure if the wires are matched correctly

so if some would be so kind as to look at their plug and let me know what color are on each side on the plug for B2S1 the plug should be close to the TB

i have 4 wires 2 white one black and one grey on the o2 side and a black, black w/brown, brown, and grey i think on the engine side

i also noticed that on the ECM only one heater wire and a signal wire are on the pin out what happen to the other heater wire ? i assume the 4th wire is a ground

thanks
 

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Discussion Starter · #4 ·
i just need you to go out and look at the connector for the 02 sensor bank 2 sensor 1 ... it is located near the TB

the sensor got hard wired in but it think its incorrect

i have 4 wires, black with red stripe brown tan and gray

i just need to know what color on the sensor side is going to which color on the engine harness side

thanks i will +rep, paypal you money if you want i just need to know asap call me or text me 414 212 5898
 

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yea i have been reading and reading and reading and reading

the code itself is p0051 which is the heater control circuit

im running VERY rich went thorough 3/4 tank 120 miles :(

im also getting misfire codes for 4,5,6 (which now to think of it thats bank 2... interesting)

i did notice that the o2 is really close to the firewall... okay ill check out the wiring all the way back to the ECU and report back

thanks


o2 sensor do not cause driveability issue if you are running that rich and the engine is misfiring there is more. i am willing to bet the car is sluggish and if so i bet your exhaust smells (rotten eggs) and if it does your o2 sensor is more in likely no longer good and your catlytic converters are overheated which means they are no longer good

i could be wrong but post more info on how the car is running

for the record o2 sensors do not cause driveability issues all you get and all you notice is a check engine light and i am a california smog technician
 

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o2 sensor do not cause driveability issue if you are running that rich and the engine is misfiring there is more. i am willing to bet the car is sluggish and if so i bet your exhaust smells (rotten eggs) and if it does your o2 sensor is more in likely no longer good and your catlytic converters are overheated which means they are no longer good
i could be wrong but post more info on how the car is running

for the record o2 sensors do not cause driveability issues all you get and all you notice is a check engine light and i am a california smog technician
Do you have headers??????????You get that smell due to having them and lack of cats...
 

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Do you have headers??????????You get that smell due to having them and lack of cats...
no it happened to me when i had stock pipes and cat i took them off and the inside was done i am a certified technician and the rotten egg smells is from the metals in the cat burning up and it usually happens when you race you car all the time and i mean all the time nothing but full throttle runs every where you go pretty much

if i had just headers and it was straight through pipes you would smell fuel well burnt fuel and thats it.... no rotten egg smell
 

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Discussion Starter · #9 ·
update the car was running rich due to a swift piggy back computer that was add when an intake was added (but now removed) so i took that out and the car runs much much better and the fuel smell is gone

however i still need to know the colors of the wires to match up, Bezik777 help me out (thanks again) but he had different wire color then me (im guessing cuz of the year difference)

so if anyone has an 03 that wouldnt mind checking it out for me real quick on their car that would be great i have black with red stripe, black, brown, and light brown/tanish
 

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okay this is what i have...... does anyone know which wires to connect?



so logically which ever wire is continuous to ground is the ground

i turn the ignition on one wire should show 12v right? (heater)

as far as the heater wires i know they work on resistance so what would happen if they were mixed

so that leaves 2 wires

i assume that the signal wire will be continuous to the signal wire on the ECM

then the remaining should be the last heater wire

does my logic hold water?
 

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o2 sensor do not cause driveability issue if you are running that rich and the engine is misfiring there is more. i am willing to bet the car is sluggish and if so i bet your exhaust smells (rotten eggs) and if it does your o2 sensor is more in likely no longer good and your catlytic converters are overheated which means they are no longer good

i could be wrong but post more info on how the car is running

for the record o2 sensors do not cause driveability issues all you get and all you notice is a check engine light and i am a california smog technician
Your wrong, a Bank 2 Sensor 1 can cause a driveability issue. you may be some smog tech but im a toyota/lexus/scion certified tech :) I have seen where an o2 sensor is messed up causing one bank to be rich or lean and it is possible to have super rich condition cause misfires.

If a unbalanced wheel can cause a missfire so can miss reading o2 sensor.
 

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Your wrong, a Bank 2 Sensor 1 can cause a driveability issue. you may be some smog tech but im a toyota/lexus/scion certified tech :) I have seen where an o2 sensor is messed up causing one bank to be rich or lean and it is possible to have super rich condition cause misfires.

If a unbalanced wheel can cause a missfire so can miss reading o2 sensor.
a super rich condition will cause a misfire but an o2 sensor will not cause driveability issues just a light and little rich if the comp. is in limp if the o2 sensor in question is an afr sensor (stock wideband) basically it could cause more issues but a narrow sensor will not casue driveability issue

P0051 Oxygen (A/F) Sensor Heater Control Circuit Low (Bank 2 Sensor 1) - DTC Code

i understand you may be a certified tech for toyota/lexus/scion but i deal with more than just one brand of car

im not saying your wrong but it depends what sensor you are working with whether its lambda or just a Zirconium sensor
 

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it would be lambda and i see it all the time with o2 sensors causing driveability issues. and what your saying does not make sense. "a super rich condition will cause a misfire but an o2 sensor will not cause driveability issues just a light and little rich if the comp."

Remember what controls fuel on our car? Umm would that be both bank 1 and 2 sensor 1. If the o2 sensors are malfunctioning and seeing too much oxygen in the exhaust whats going to happen.....they will compensate and richen up the the car. When this happens a P0171 or P0174 system lean will be the CEL because of the malfunctioning o2 sensors.

if its a super lean condition because the o2 sensors are miss reading information the CEL will come on for a P0171 or P0174 and the fuel mixture will go full rich and can cause a P0300 or individual cylinder missfires for a rich condition. So actually to the computer the o2 sensors are working so a o2 code might not be present but that doesnt mean that its not the problem. so you have a system lean code and the car is going rich and missfiring. This can also happen with a system rich code P0172 and P0175 and the engine will actually missfire due to fuel being pulled away. and we all know what happens when motors go lean. So yes an o2 sensor can cause a driveability issue without tripping the CEL for an o2 code.

so ignoring a CEL or an o2 code is not the best thing to do. If the car were to go rich whats the first thing to go?.....the cat and then when thats gone and a P0420 is now present and the car is still missfiring. at this point your in a whole world of hurt and things are going to get expensive cause you ignored just a little light bulb.

you may work on a wide veriety of cars and thats cool but i work with one manufacture every day and i know alot about diagnostic procedures. I am still learning and always will be but i hate to say this but I have access to more diagnostic information about Toyota, Lexus, and Scion then you or most people. im not trying to be an ass about it but there are a few members on here that I have worked with and can support me with what I am saying.

Oh and when you get an o2 sensor with a heater circut code 90% of the time the o2 sensor is the problem and needs to be replaced. You are right tho, a heater circuit wont cause a driveability issue. The heater circuit on a toyota o2 sensor is only used for cold starts/emission perposes and does not affect the reading of an o2 sensor. But what I said above is to prove to you that an o2 sensor can cause driveability issues. it may not be the problem for this member but i wanted to explain to you that they can cause problems and actually trip a different DTC's but still be the problem.
 

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it would be lambda and i see it all the time with o2 sensors causing driveability issues. and what your saying does not make sense. "a super rich condition will cause a misfire but an o2 sensor will not cause driveability issues just a light and little rich if the comp."

Remember what controls fuel on our car? Umm would that be both bank 1 and 2 sensor 1. If the o2 sensors are malfunctioning and seeing too much oxygen in the exhaust whats going to happen.....they will compensate and richen up the the car. if its a super lean condition because the o2 sensors are miss reading information the CEL will come on and the fuel mixture will go full rich and can cause a P0300 or individual cylinder missfires. so ignoring a o2 code is not the best thing to do. when the car goes rich whats the first thing to go.....the cat and then when thats gone and a P0420 is now present and the car is still missfiring and now your in a whole world of hurt. you may work on a ton of cars and thats cool but i work with one manufacture every day and i know everything in and out and i have access to more information then you every will when it comes to Toyota, Lexus, and Scion.
you supported your arguement with correct information and i know the o2 sensor controls fuel but the main purpose of the o2 is to switch fuel for the functionality of the cat if you look at the list of importance of sensors meaning wich sensor the ecu refers to first the o2 sesor would be last on that list. the o2 sensor has little control over fuel unless it is a lambda sensor
but i relize we are arguing different sides of the same point so i will end it here.... ++++rep thank you for backing you side up

and the statement i made is correct if it is NOT a lambda sensor
 

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your still an idiot and im done trying to correct you. All you are is a smog tech and thats it, you dont fix cars like I do and when I see motors come in for a bad missfire cause by a miss reading o2 sensor i know for a fact that and o2 sensor is a very important sensor.

An o2 sensor and your mass air flow meter are 2 most important things your engine uses to control fuel delivery. so your wrong again, the o2 sensor is not last on the list. I would say its tied for first.
 

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your still an idiot and im done trying to correct you. All you are is a smog tech and thats it, you dont fix cars like I do and when I see motors come in for a bad missfire cause by a miss reading o2 sensor i know for a fact that and o2 sensor is a very important sensor.

An o2 sensor and your mass air flow meter are 2 most important things your engine uses to control fuel delivery. so your wrong again, the o2 sensor is not last on the list. I would say its tied for first.
so were now were calling each other names huh well thats kool and i am test and repair and you are wrong first sensor of priority is the crank signal that give the ecu which table to be in than maf it refines the tune in the table o2s does small corrections but if you wanna call names why dont we meet up than call names plus i gave you pos rep cause your info wasnt wrong i am not an idiot i know what i am talking about douche

your talking from personal experience i know from fact
 
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