I have a 16v, mine was an original Bosch 0258003060 one?
The normal wiring is as follows
white = 12v for heating, paired
black = the signal, on it's own
I would run the car and test with a DMM on the black wire from the lambda sensor for a signal that should be between 0.2-0.8v, anything between 1v, should be about 0.45v when connected and engine running. From the car loom side the other wires should output 12v
This will cause the ecu to hold a fault so reset it "by disconnecting the battery for 10 or more seconds" before you go further.
With it all connected and the car running you should see fluctuation on the black wire 0.6 - 0.8 -0.2 again should be around 0.45v
Does your replacement not have the same connections, as in single black wire and paired other wires?
I have only ever tested the heating circuit in relation to each other, as in the 2 wires. I would think that it doesnt matter which way they are connected but if you want you could check your car wiring loom, in relation th earth to find out which one is - and which one is + and connect to the lambda sensor with red = + and white being - , this is an assumption and could be confirmed by having it connected, ignition on and lambda sensor in your hand, it should heat up, please don't burn yourself
Last edited by BigAl33; 03-12-09 at 09:38.