wiring universal lambda sensor

[yohan]

hey guys
i changed my lambda sensor on my s2 aby, and the new one is bosch but has the universal plug, its a 3 wire job and instead of just cutting the cables and putting an extra plug in, i decided to replace the original plugs with it, so that there is only 1 connection in the engine bay to eliminate any future problems with those old connectors.
however this is a slightly confusing bit for me. there is the 2 pin connector which i guess is for the lambda heater? then the other one is a single plug but there were 2 wires behind it. I would have thought these would connect together in the plug, but this doesnt seem so obvious in the wiring diagrams. does anyone know what this dotted circle means on the wire leading to the sensor? any help would be so great! thanks lambda.PNG

[s2_bo]

So is your new lambda a 4 wire probe? Because up it says 3 wire at first in your post and then later you said that the single plug (spade connector) has also got two wires coming from it? Is this going to the probe or is it coming from the loom to the plug?


The S2 uses a 3 wire prob. So you should only have 2 wires from the double connector (black) and one wire from the single connector (white) Maybe you have an extra wire for an AFR gauge?

[yohan]

the new sensor has 3 wires; 2 white and 1 black, same as the original. The 2 white wires go into the 2 pin connector as the instructions showed and the black one into the separate single connector. the single connector has 2 wires coming from the loom. any ideas? thanks

[s2_bo]

Ahh sorry I got the colour mixed up.

Not sure why your loom would have two connections from the back of the single connector. My car has this but one is for the narrow band AFR gauge.

Maybe just wire it up like you have described above and it should work fine...

[Gazjen]

Could anyone have linked in for a gauge?

White is normally heater and black is sensor wire

[yohan]

hhhmm i dont think anyones had a gauge attached but iv wired them both up anyway although im not sure if its working right especially since the maf sensor is (and possibly other sensors) playing up as well and emissions are even worse then before. So its off to the local Audi specialist for a full diagnostics check and hopefully they can get the car back to running right.