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all plugs are original and all O2 sensors are OEM Bosch with plugs. No pig tails. I just need to find out where each one goes so I can finally get them hooked up correctly and the engine light will (hopefully) quit giving me O2 sensor codes. Thanks
You have B2S1 listed twice. Which wire goes to B1S3, red or white?
That is exactly how mine are currently hooked up. I just put in a new sensor behind converter (B1S3 or B2S2), cleared code with my OBD2 scan tool and light came back on. code P0146 (no activity detected, bank 1 sensor 3) and P0151 (low voltage bank 2 sensor 1). Also, does your diagram indicate that B2S1 is Drivers side down pipe or before converter ? Im reading it as B1S1 passenger side down pipe, B2S1 Drivers side down pipe, B1S2 drivers side before converter, and B1S3 drivers side after converter. That is why its so confusing. There is only one sensor on passenger side, yet everyone says that is bank 1 when there are 3 bank 1 sensors and only 1 bank 2 sensor, which you say, is mixed in with the other bank 1 sensors on drivers side.
Lets just stick to your diagram to prevent more confusion as it does not list a B2S3 nor does any scan tool. my engine codes list it as B1S3 . This doesnt seem to be solving my issue and according to your info, I have them in the right locations. where does your info say code 0146 and 0151 are and what else would cause those codes to be coming up after installing new sensors? The wiring harness and plugs are in good shape as far as I can see. No breaks or melted parts. nothing against exhaust. Is there a relay or fuse that could be bad that just happen to control those 2 sensors?
Ok. these are 4 wire plugs and some have at least one same color,ie, green or red. you only listed 1 color per plug so I may not have them hooked up correctly since i just noticed that 2 plugs have a green wire for instance.
My after cat converter wires (B1S3) are green, red and black (i'll just list 3 wires because they all seem to have a red wire with blue stripe as the 4th).
The drivers side down pipe (B2S1) wires are red, white and black.
before converter (B1S2) are green, blue, black.
Passenger side down pipe (B1S1) are pink, blue, black.
Can you write the location under each sensor? B1S1, B1S2 etc.
The wiring diagram doesnt say. Thanks
I meant on the diagram but it is listed on there, it was just printed very small and I missed it.
Ok, now we're getting somewhere. My, B1S3 and B2S1 plugs seem to be reversed, as I thought. I'll switch them and see if it works and will update you. Thanks.
Problem, diagram lists 2 sensors with green and red wire when 1 should be green and blue. Also, it says the B1S3 should be red and white wires but that plug is no way near long enough to reach it. That plug is only about 3 inches long coming off the front of the wiring harness and will only reach B2S1 or B1S2.
all of the plugs will reach B2S1 and B1S2 but only the Green/red and green/blue plugs will reach B1S3
Yes, there is a plug with a white and red wires. that is the one that you said goes to B1S3 but it is too short to reach. Im wondering if this diagram is wrong because it differs from the one that the other tech on this site gave me. his have all the right plug colors but it was for an auto transmission and are labeled for different locations. Also, your diagram does not list a plug with a blue and green wire like mine has but instead list 2 plugs with red and green wires. it could just be a typo but i still need to know where that blue and green plug go.
Manufacturers date is November 1995.
But does it show the blue and red on any of the manual trans diagram? I'm guessing not if all of them show 2 plugs with red and green. I'm beginning to wonder if this car has the auto trans wire harness and they changed the transmission at factory. Maybe a special order or something after the car was almost complete. Is ecm under dash behind glove box, as usual?
There is no way red and white will reach. plus the fact that I dont have 2 plugs with red and green. thats why I said, im wondering if somehow they put the auto trans wiring harness in at factory with the manual trans, thus all the confusion.
yes, I agree that tracing back to ECM is the way to go. is it under dash behind glove box?
D!3 is green and D12 is blue on bottom row of white connector.
Thanks for staying with me on this. 3 auto shops and the isuzu dealer couldnt figure it out 9 years ago and Ive been trying to get it right ever since. all because a mechanic didnt label them before disconnecting them :(
I still have a feeling the harness is for an auto tranny, its the only logical explanation but I want to be sure. I dont want to melt the converter because of the sensors being wrong again.
I think it will. Seems like I remember going back and forth between B1S2 & B1S3 and the red/green and red/blue plugs. I think I have it hooked to B1S3 now actually because I think it was a shade longer than the red/green plug but I wont be able to get under the car until the weekend. I work 10 hour nights and just got home and decided to uncover the ECM since it was a quick, clean job. I'll let you know what I find then.
What did you come up with if it does reach?
well, they all must be wrong then because, remember, it calls for the red/white plug to go there not one of the 2 "typo" red/green plugs.
So, based on your info, pin out, etc. what is the correct order?
Im pretty sure this is how I have it hooked up right now, but will make sure on Sat. Tell me if it is the same as what you are coming up with.
B1S1 : Pink/blue B2S1:red/white
If so, it doesnt match either diagram, Auto or Manual transmission.
The auto transmission is close but lists green/blue to B1S2 and red/green to B1S3. No wonder its so confusing.
No kidding on the diagrams, that was my point ;)
Glad we're figuring it out. Seeing that pin location makes me feel good. My next step was going to be, unplug one and wait for engine light to come on, then check code location and repeat 3 more times. No fun and waste of gas and time.
Do you have the rest of the pin legend showing the other sensors for manual trans?
Thanks for your patience and tenacity.
ok. I will check it all out on sat along with replacing the final 2 sensors with new ones and let you know what happens.
BTW, do you know what the drive cycle is on this vehichle after clearing the codes, for it to go back into "ready mode". The state will not pass the emissions test on it until the ECM goes back into ready mode after clearing codes which is done by driving it a certain distance and every cars drive cycle seems to be different on this subject.
I think that did the trick. I changed the 2 remaining sensors and plugged all 4 back the I had them in my last post. So far, no engine light after about 20 miles.
Thanks for hanging in there and helping me trace the correct wires.