Dear fellows, Hope you are all safe and enjoying your rides.

Recently my Skoda fabia 1.2 HTP MK2 5J(Pre Facelift) 70kKms engine idle started to feel little rought so read the codes using obd bluetooth adapter with torque app.

Got P0031 and P0036 so after removing and checking the post cat lambda sensors (which only came off easily) when tested using multimeter the heater circuit white wire the circuit was open so I've finalised that the heater element is faulty and with the code it looked like the sensor not giving proper values to the ECU.

While checking for replacements the part numbers were

Pre Cat - VWAG 03E 906 262 B 12V 

Post Cat - VWAG 03E 906 262 C 12V

Only the B and C were different but both sensors have same color coded 4 wires and look kind of same.

But the post cat was available online for around 40$USD(2700 Indian Rupees) and the pre cat was not available (still listed for   900USD which i will never gonna buy).

My question is are those both pre and post cat lambda sensors are interchangeable? 

If no, Any generic sensor available? Or any alternative from VAG OEM?

Thanks in advance and happy holidays.

I think the difference may just be in cable lengths and possibly connector types. 

 

What's your engine code, you seem to have some slightly different ones in India?

 

You can find this code on the sticker with the build data on the trunk floor, or maybe on a sticker on top of the chain cover.

10 hours ago, Wino said:

I think the difference may just be in cable lengths and possibly connector types. 

 

What's your engine code, you seem to have some slightly different ones in India?

 

You can find this code on the sticker with the build data on the trunk floor, or maybe on a sticker on top of the chain cover.

Thanks for the reply.

 

My Engine code is:  CEVA 51KW 70HP 1.2Ltr 3Cylinder Date:01/07-09/10 Model: Fabia MK2 5J 1.2 HTP.

Regarding the connector both sensor have same connector with same colour of wires  In My case the connector from the car loom for post cat was destroyed and connected only using bare ISO pins, 

Removed post cat lambda sensor of skoda fabia mk2 1.2htp, Part Number : VWAG 03E 906 262 C 12V:

 

Skoda fabia Pre cat lambda sensor part number :VWAG 03E 906 262 B 12V:

 

lambda sensor connector loom for reference.

Edited 21 December, 20205 yr by Vigneshwaran

I'm a bit confused by what you have fitted in each position, because this diagram claims the you should have 03E 906 262C fitted pre-cat, and 03C 906 262 fitted post-cat on CEVA.

Item numbers 1 & 6 respectively here lambda probe; (behind catalyst) - Fabia(FABI) [EUROPA 2010 year] (7zap.com)

 

If you go to the furthest right column there is a button with horizontal opposing arrows which shows aftermarket equivalent parts for each. For 03E906262C, 03E906262B is shown as interchangeable. For 03C906262 there seem to be hundreds of equivalents. 

 

I get the impression that if it has the right number of wires in correct positions within right connector,  and a cable that will reach, it will do the job.

 

 

Sorry for the confusion, There is a chance the sensors may have messed up since I bought this car used and it may have been repaired in local shops where they have fitted the wrong sensors, As you have suggested I will look for alternatives and will put proper sensor on each of the slots.

From what I know the heating coil can be tested for continuity to check if they work or not, Is there  a simple way to check if the oxygen sensor work (the other two grey and black wires) ?  except the ECU codes? 

After searching for a while I do not think that they are interchangeable due to unavailability of information on how these sensors work internally especially the VAG ones.

Thanks you for the explanation now I getting familiar with using 7Zap.com, I have one doubt in 7zap.com link, The diagram shows 4 cylinders instead of 3, Do we have to be concerned about it?

The diagrams are often shared between several engine types, so no concern there.

I don't know of another way to test the oxygen-sensing parts other than fit to car and look for fault codes or look at measuring blocks in VCDS to watch live values.