Dear Community, dear Crasher,


I need your help again.


I almost figured out everything on my car and I am close not to have any error or issue in any of the controllers in my car.. but..

But I still have one (hopefully last..) issue with the car.


The car: Seat Toldeo 1.6 16V AZD engine code (same as Golf MK4 and Bora)
I have a "sporadical" upstream lambda sensor heater malfunction fault code:

17604 - Oxygen (Lambda) Sensor Heater Circuit: B1 S1
P1196 - 35-00 - Electrical Malfunction

Sporadical means sometimes if I delete the code it won't come back in 100+km of driving,
sometimes after code clearing it pops up almost immediately again..

There are no other codes, no drivability issues, nothing at all, setting the readiness bits are easy as 123 when the lambda heater test does not give a fault code..

VCDS meas. block 041 is telling me that the resistance of the sensor heater element (with warmed up engine) is around 83..90 Ohms and one guy here who has a BCB engine told me that he has the same reading (and as far as I know both AZD and BCB are sharing the same genuine part numbers in terms of lambda sensors)


So the million quid/dollar/Forint/EUR question is:

If I would drive my car to your garage (what is not really possible since we are at least 1000 miles away unfortunately..) to diagnose the issue what whould you do? What steps would you take to rule out things to get closer to the resolution?


Thank you!!