Lambda sensor location

[yazmidani]

Hi there folks, was driving as normal yesterday when my MIL light came on, did a quick scan this morning and this error code came up -
1 Fault Found:
000054 - Oxygen (Lambda) Sensor B1 S2: Heating Circuit: Malfunction / Open Circuit
P0036 - 004 - No Signal/Communication - MIL ON
Freeze Frame:
Fault Status: 11100100
Fault Priority: 0
Fault Frequency: 1
Mileage: 32124 km
Time Indication: 0
Date: 2000.00.00
Time: 14:38:34

Just wondering if anyone knows the location of this sensor?
Also I have a copy of Elsawin from ebay, never really worked out how to use it if anyone has any tips lol

Just to let you know I've still got a standard cat fitted, as I have read sometime's having a decat may bring this up?

I'm not sure if a cable has come loose, as it says there is no signal. .

Anyways enough rambling, thanks for reading. . .

 

[DanGB]

Theres the pre cat and post cat, the post cat is accesable from under the car, and the precat can be reached from at the back of the engine from the top.
Cant remember off hand which one B1 S2 is though. Elsawin should tell you I think.

 

[yazmidani]

Thanks for that Dan, I'll go out and have a look now and see if I can find something loose. . .Hopefully!!!

 

[m0rk]

Should be post cat

 

[yazmidani]

Well I've had a look around both of them, and checked the connectors, and everything looks ok. . .
Is there a way I can test them to find out 100% which one it is? Although I think I agree about it being post Cat, I'd like to know before I go and buy another one. . .

 

[Ryan20]

what is a lambda sensor?

Ryan

 

[yazmidani]

what is a lambda sensor?

Ryan

Well as I know they are sensors(two in this case) in the exhaust system that measure the Air/Fuel ratio, and then send a message to the ECU telling it if it needs to alter the mixture so the car runs as it should. .

Or at least that my understanding of them, you could always google
Or someone else may be able to explain it better?

 

[csd_19]

Well as I know they are sensors(two in this case) in the exhaust system that measure the Air/Fuel ratio, and then send a message to the ECU telling it if it needs to alter the mixture so the car runs as it should. .

Or at least that my understanding of them, you could always google
Or someone else may be able to explain it better?

Yep

Usually the pre-cat one measures the air/fuel and tells the ecu if the car is running rich or lean, the post-cat one is just a "tell tale" to verify the cat is working correctly.

It's the second lambda sensor that throws up the MIL when you fit a decat

 

[yazmidani]

There we are thanks for that csd. . .

 

[yazmidani]

Update:

After checking the wiring and running a few tests in vag-com It looked like a dead sensor,
so I bought another one and fitted it today.

After about ten mins of driving the MIL light comes on again!!!
I decided to log it in vagcom and I'm now very confused!

The error message says No signal/communication, but In vagcom I was watching live readings and the value was constantly changing, unlike before.

So now I don't get whats going on? Car says it can't communicate with it, but vagcom can read it.

Can anyone shed any light on this please ??
Thanks

 

[Nath.]

Update:

After checking the wiring and running a few tests in vag-com It looked like a dead sensor,
so I bought another one and fitted it today.

After about ten mins of driving the MIL light comes on again!!!
I decided to log it in vagcom and I'm now very confused!

The error message says No signal/communication, but In vagcom I was watching live readings and the value was constantly changing, unlike before.

So now I don't get whats going on? Car says it can't communicate with it, but vagcom can read it.

Can anyone shed any light on this please ??
Thanks

The sensor you have fitted is probably fine but the ECU will trow a wobbly if the readings form the sensor are out of range, personally I think I would replace the other Lambda sensor and see where that gets you.

 

[yazmidani]

The sensor you have fitted is probably fine but the ECU will trow a wobbly if the readings form the sensor are out of range, personally I think I would replace the other Lambda sensor and see where that gets you.

I am considering that now, but if anyone has any other idea's I'm open to suggestions as they're quite expensive, and it seems to be working perfectly fine. (the first one)

Is there a way to reset the ECU? Leave the battery disconnected or something simple like that??

 

[Tfsi_Mike]

Did you get his sorted mate?

I have B1 Sensor 2 fault too. It happened when fitting De cat but after re fitting cat and clearing fault code it still comes back

 

[DanGB]

Did you get his sorted mate?

I have B1 Sensor 2 fault too. It happened when fitting De cat but after re fitting cat and clearing fault code it still comes back

Ive got a B1 sensor 1 (pre cat) fault at the moment. Looks like im going to have to replace mine (£92!)

 

[Tfsi_Mike]

Has it caused you any noteable problems Dan?

 

[DanGB]

Not sure really, The car is running like crap with misfiring etc, not sure if its to do with the sensor though. I'll replace it soon. not driving the car at the moment.

 

[Fusster]

I am considering that now, but if anyone has any other idea's I'm open to suggestions as they're quite expensive, and it seems to be working perfectly fine. (the first one)

Is there a way to reset the ECU? Leave the battery disconnected or something simple like that??

Your original fault is for bank 1 sensor 2 which is the rear sensor after the cat,as someone else said its function is to monitor the cat,It is a 4 wire sensor,pin 1 and 2 are the heater circuit wires,it is fed from fuse 48,put a meter across pin 1 and 2 with the engine running and check you have 12 volts there.
If you have then the sensor is the problem,have you fitted a genuine sensor as the non gen ones are rubbish...
The front sensor will not influence a rear sensor fault so dont waste your money,
It should read a steadyish .5v if the cat is doing its job.
the front sensor is a 6 wire sensor and works in a entirley diffrent way(current draw).
Refit your old sensor and if the fault that returns is your original fault then you must have a faulty sensor,also check fuse 48.
hope this helps

 

[Tfsi_Mike]

Thats useful thanks. Will check fuse 48 too. Im looking at at Bosch one from euro car parts...

An OEM part?

 

[Tfsi_Mike]

Fuse 48 is ok.

 

[Fusster]

What is the actual fault code ?.
tbh when i replied to this i didn,t notice the thread was old...hehe.
anyhow let me know the fault code and we can go from there
cheers