Lambda wires

[daveb500]

When I did my engine rebuild, I did a fair bit of rewiring and I want to double-check that the wires to the lambda sensors are correct. The lamda has 3 coloured wires - Red, White and Black. I am thinking that one is earth (black?), one is 12v positive (red?) and one is the lambda reading (white?). Is that correct?

[steve-V8s]

http://www.cats-direct-shop.co.uk/lambda-sensors.p...

[daveb500]

steve-V8s said:

http://www.cats-direct-shop.co.uk/lambda-sensors.p...

Interesting.....but none of them are the same as ours.

[steve-V8s]

If you have a poke about the site somewhere I think you will find Black is universally used as the output. I seem to remember that on the standard ones the other two are for the heater and the signal ground is via the block. Should be able to check that later as I did a drawing of the old loom when it came out. If no one else replies before get home I will dig out the notes.

[daveb500]

steve-V8s said:

If you have a poke about the site somewhere I think you will find Black is universally used as the output. I seem to remember that on the standard ones the other two are for the heater and the signal ground is via the block. Should be able to check that later as I did a drawing of the old loom when it came out. If no one else replies before get home I will dig out the notes.

Thanks Steve - very much appreciated

[blitzracing]

The mans correct, black is output, red heater supply, white common ground

[steve-V8s]

There you are then.

Mark knows what he is about with the electrical bits. I still think the signal ground is via the block but it will make no odds provided you connect white to ground.

[daveb500]

blitzracing said:

The mans correct, black is output, red heater supply, white common ground

Ta very much

[blitzracing]

steve-V8s said:

There you are then.

Mark knows what he is about with the electrical bits. I still think the signal ground is via the block but it will make no odds provided you connect white to ground.

The lambda earth is also fed back along a screen shield around the signal wire at feeds back to the ECU. This must be connected as the voltages are very small, and if the block and chassis was the only ground path electrical interfearance would become a problem. Its not obvious, as a normal connector wire is joined to it inside the loom and apears in the back of the lambda plug / socket connector, and its worth noting that every sensor wire has its own ground wire back to the ECU to ensure the correct voltages are maintained.