MY CAR IS A 2003 HONDA ACCORD EX(4CYL, 2.4). THE ENGINE LIGHT HAS BEEN ON IT FOR MONTHS. MY MECHANIC SCANNED IT WITH HIS COMPUTER. IT READ: P0141 O2 SENSOR HEATER CIRCUIT BANK 1 SENSOR 2. I WENT TO ADVANCED AUTO PARTS IN CHICAGO,ILL. THEY TOLD ME THT MY CAR HAS 3 SENSORS. AND THAT I NEEDED THE UPSTREAM SENSOR(BEFORE THE CONVERTER). I PURCHASED IT AND MY MECHANIC PUT IT IN. MEANWHILE, THE ENGINE LIGHT IS STILL ON AND THEN 3 DAYS LATER , THE SAME CODE POPPED OUT IN THE SCANNER. THE AUTO PARTS PLACE TOLD ME-MY MECHANIC MUST OF PUT IN THE WRONG ONE. I AM SO FRUSTRATED!!!!! I THEN TOOK MY CAR TO THE SHELL STATION AND THEY TOLD ME I HAVE 2 SENSORS AND THE ONE I NEED IS SENSOR 2( THE ONE AFTER THE CONVERTER). I CALLED TWO OTHER MECHANIC SHOPS AND WAS TOLD THE SAME THING. PLEASE TELL ME IF MY CAR HAS 2 OR 3 SENSORS?? AND WHICH IS THE SENSOR I REALLY NEED-BEFORE OR AFTER?? THE DEALER WANTS TO CHARGE ME AN ARM AND A LEG!!!!!!!! IF YOU COULD POST A DIAGRAM OF MY CAR -LIKE THE EXHAUST SYSTEM OR WHATEVER SHOWS THE SENSORS, THANKYOU.

 

Ignore bank 1. That is only important in a V6. Sensor 2 is the sensor after the catalytic converter. It monitors the cat's performance.

The heater circuit is easy to check. You can unplug the sensor and ohm the blk and blk wires on the sensor. Should have just a few ohms. If you get OL ( out of limit ) or very high ( more than a few ohms ) on your multimeter, replace the sensor. If the sensor is ok, there could be a problem elswhere in the wiring. Unless you have a rat chew issue or someone stole the fuse for the heater circuit, the sensor is probably bad.

 

BTW, your car only has 2 sensors.

 

My 03 accord had the same code/problem. Its a quick fix and phootbag pretty much has it nailed on how to diagnose your p0141 code. At least your check engine light has only been on for a few months. Mine was on for over a year and a half.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by phootbag &raquo;</TD></TR><TR><TD CLASS="quote">BTW, your car only has 2 sensors. </TD></TR></TABLE>

yeah but i think the parts listing has three. the secondary is comes in two different legnth wires. normal and the one with the connector is under the seat. cannot tell u how many times parts ordered me the wrong one.

 

Hello

My car is Honda Accord EX 2003, after the check engine light they read a code - downstream sensor. Replaced. After 5 minutes light come back, now computer is showing upstream sensor. Replaced. And the check engine light is back after 40 minutes
.
What else can be wrong?? Any suggestions?
Thanks guys!


Ok, now I'm almost sure - computer, i went to few more places, people told me its computer fault,only honda dealer can do that


Modified by pacmanek at 6:36 AM 9/11/2008

 

check your fuses/wiring for the heater circui. Chances are you popped a fuse or have a open in a wire somewhere. I beleive it is fuse 4 (15a) under the dash, also check the wiring between the sensor/fuse panel, and there is a A/F meter relay, try switching out with one that works (i.e. the one operates your power windows)

 

The only time a dealership is a BAD place to take your vehicle is when the people there don't know what they are doing. If you have a dealer near you that has knowledgable and honest people, I'd take your vechicle there. They usually have more information regarding diagnosing and repairing your vehicle than most other places out there.

The nature of your problem, you probably have the best luck at getting it properly diagnosed at a dealer. I have never seen a computer need to be replaced on your year accord because of an oxygen sensor DTC.

 

Hey all, Sorry for digging up an old thread but I found this post through a google search and it is exactly what I'm dealing with. Bank 1 sensor 2 has gone bad. I picked up a new Bosch sensor at Advance and am all ready to replace (no big deal replacing o2 sensors right?)...well the cord goes through a little rubber grommet/boot and up into the frame...how the heck do you get to the connector??? That be my only problem...how to get to the connector. Any help would be greatly appreciated.


Thanks,
Huck

 

Oh and I've got close to 142k miles on the vehicle if that matters.

 

It's under the carpet beneath the front passenger seat.

 

Thanks! I installed the new o2 sensor last Saturday and the check engine light went off about 30 mins into my hour drive. Makes me feel good. Thanks again for the help and great site!