Hello everyone.
I'm trying to deal with annoying problem for which I can't see bright light in the end of the tunnel.
I've recently changed o2 sensor, the problem is, p0141 comes straight up after ignition. BUT! It doesn't when car engine is hot, I assume the problem is either with sensor heater or voltage from the car to the sensor. After digging in the net I found, that o2 sensor has a fuse and I found it in passenger side fuse box with name LAF heater. BUT! Again that annoying butt, there was no fuse...and the worst part is, that the socket is very deep inside(basically showing, that it's not being used) like any other fuse-less socket, while if I take out a fuse next to it, the socket is visibly close. One more thing, when I was installing sensor, I checked heating element wires with tester and it beeped, as in short circuit. Now, firstly sorry for making no sense. Secondly, could anybody please suggest anything on this issue? Or should get under my car again to check heater voltage? Should I try to get to the fuse socket and force connect it?

To sum things up:
Cold car = MIL - p0141
Hot car = MIL - OK
LAF heater fuse(20A) - not present
LAF heater socket - buried deep inside
_______________________
Solution for cold car = ???

P.S. o2 sensor is new unused before. Any help appreciated, thank you in advance.

Some updates:
Took out sensor and turned on engine, lambda wasn't heating up, tried to connect heater element straight to battery, lambda did become hot. Then I checked voltage of lambda socket on running engine and it was 6-8 v and was gone to zero after 5 seconds after ignition.

Conclusion:
Lambda sensor - 100% working
Heater voltage unstable and stops after 5 seconds. I'm planning to pass 12 volts from ignition. I don't know if it's wise to put constant 12 volts on lambda heater, so I would really REALLY appreciate any better idea.

 

I'm going off a US accord shop manual. The code you are getting is for the secondary O2 sensor that is bolted to the catalytic converter. Is that the sensor with issues on your car?

The blk/yel wire going to the O2 sensor should have 12V with the key in the II position to body ground. Is the connector under one of the front seats in the vehicle?

The fuse is listed as the ECM (ECM/PCM) Cruise Control 15amp. In the US accord it is in the driver's side fuse box and is labeled fuse #6. Check the fuse and check that one of the fuse pins has 12V.

EDIT: I would try to figure out what is wrong with the wiring/fuse before trying to bypass an electrical system in your car.

 

Hello. Thank you for your reply. It is the 2nd sensor, which is mounted after cat that's why I changed it in first place. Firstly, my sensor has 4 wires - black, grey and 2 white. I'm from UK, so my car steering is on right side. Just to make sure I checked all fuses in both boxes and under hood. They are all working. I checked voltage between 2 white wires and it was 6-8 volts only after ignition and only for about 5 seconds, when I was changing key position from 1 to 2, voltage was changing only from 0 to 0,04 volts. The only thing I had in fuses was laf heater 20amp, passenger side fuse box, as was mentioned in internet it is responsible for o2 sensor heater. But it had no fuse in it and pins are very deep inside the fuse box like it is not used. Forgive me for chaotic message, I'll try to sum things up now.

2nd Lambda sensor after cat is new and working.
Tests done so far:
Lambda taken out of cat while still connected to the wire, after ignition lambda remains cold. Lambda 2 white wires connected to the battery directly for short time - lambda sensor heats up. Was connected though tester and showed 1.25 amp.
Here's how my lambda looks like
So if socket looks like this:
1 2
3 4
Then 1 is black, 2 - grey, 3 and 4 white
Same test but without lambda connected, measuring voltage between 2 white on car socket. After ignition, voltage was about 7 volts, but drops to 0 after around 5 seconds.

So in the end, i got fully working lambda, which works perfectly on hot engine and it heats up on direct battery connection, i got weird voltage output which stops after around 5 sec. Which makes me think it can't be fuse, since it does give voltage output, even if wrong one. But in this paradox i don't know what to do next. I really want those 12v on lambda heater, but i still wish it to remain controlled, since voltage depends on engine temperature. So if you could suggest what could cause that voltage sudden drop down or at least where to look for an answer, i would really appreciate it. Thank you for your help

 

You described the wire colors on the sensor side of the plug. What are the wire colors on the engine harness side of the plug?

 

They are black-white, black-yellow. Black-yellow is ground, sorry my technical English is horrible i hope i make sense, but i found out, that it's ground by connecting tester to lambda socket and minus on battery. After some thinking, there's only one wire malfunction. Since i got ground and since computer receives data from lambda on hot engine, then the other 2 wires should be fine. I'm planning to trace where white-black wire goes inside the car and see what's causing the voltage instability

 

I'm not at my personal computer with access to the shop manual to look at wire colors. You may also want to trace the blk/yel wire, since it matches the color on the US accord and has ground without voltage.

Regardless, the secondary O2 sensor doesn't affect engine performance, just monitors the catalytic converter for emissions.

 

It doesn't? O: i thought it regulates the air/fuel intake depending on emission?

 

The lambda sensor upstream regulates the air/fuel mixture (aka primary O2 sensor). The sensor in the catalytic converter is the older O2 sensor that is less expensive and ensures the catalytic converter is working properly. That is how they are setup in the USA Accords.

 

Awch and was hoping tosave fuel after fixing the issue =D regardless i want to get rid of the Mil poping up all the time. I did find the cruise control fuse, haven't checked the voltage though, didn't had time. In amy case, thank you for your help and assistance